Examining theory-practice gap in implementing differentiated instruction (DI) in the Ethiopian TVET system: the case of TVET colleges in Bahir Dar City

Abstract The objective of this study was to examine the theory-practice gap in implementing DI. To this end, a mixed research design was used. The data sources were TVET teachers, college Deans, and the regional TVED experts in Bahir Dar city. Questionnaire, FGD, and document analysis were used to gather data. Then statistical tools including percentage, mean, standard deviation, one sample t-test, independent samples t-test, and one way ANOVA were employed to analyze the data. The findings indicate that the TVET system recognizes the principles of DI in its national level documents such as the strategy, curriculum, and TTLM preparation. It was also found that male TVET trainers’ understanding and practice of DI was higher than their female counterparts. Another finding was that the mean of Diploma holder (Level IV) teachers’ understanding and practice of the principles of DI is greater than that of the corresponding First Degree and Second Degree holders. Generally, the practice of the principles of DI in the TVET system was found poor. Planning time, shortage of materials, large class size, and lack of school administration support were among the factors obstructing the implementation of DI. In this regard, some possible suggestions are recommended in this article.

Solomon Melesse has been teaching at different levels for the last 28 years. In his stay at the current institution where he is working now, he had been working as a course chair, Department Head, Vice Dean and Acting Dean of the College of Education and Behavioral Sciences, Bahir Dar University. He published more than 50 articles, and 6 Book Chapters in the area of Curriculum, Instruction, and Teacher Education. He is now Professor of Curriculum and Instruction at Bahir Dar University, the historic home of pedagogics in East Africa.

PUBLIC INTEREST STATEMENT
This study was designed to examine the discrepancy between practitioners' level of understanding and practicing the principles of differentiated instruction (DI) in the TVET system. To this end, a mixed research design was used. The data sources were TVET teachers, college Deans, and the regional TVED experts. Questionnaire, FGD, and document analysis were the major data collection tools. The collected data was analyzed using appropriate statistical tools. The findings indicate that the practice of the principles of DI in the system was found poor. Shortage of planning time and materials, large class size, and lack of support were among the factors that obstructed the implementation of DI in the system. To improve the situation, some possible suggestions were forwarded in the article.

Background of the study
Schools are the properties of the respective community. The community sends their children to schools with the belief that they can learn and develop and with promise that they have the potential to learn and develop. On the other hand, it is well known that every student in a given class does not have the same interest and ability and learning style. According to Rasheed and Wahid (2018), every student differs in his/her approach towards studies, even inside a single classroom, the thought process, the perception towards the content being delivered, the type of content being delivered, emotional stability, the sequence of instruction being delivered each and every thing related to the instruction. They added, "Not each student learns from the same resource, the same process and same sequence; each of us is different in nature; time and again, it has been proved that one size doesn't fit all, neither clothes nor shoes and so does the differences apply to instruction as well."(p. 1). Still another important fact is that currently employers and, of course, governments are putting expectations or standards that schools and individual students should meet. This necessitates a means to be devised so that every student could enjoy learning to her/his potential. Hence, many scholars/schools were searching for instructional strategies to meet the needs of all learners while adhering to the standards of the frameworks (Ann, 2012).Hence, differentiated instruction (DI) comes as a way for teachers to provide instruction and track progress at each student's instructional level in order to meet these standards (Ann, 2012).
Differentiated Instruction (DI) is an approach to teaching and learning that gives students multiple options for taking in information and making sense of ideas (Tomlinson & Imbeau, 2010). It is a balanced emphasis on individual students' course content (Tomlinson & Imbeau, 2010), a philosophy of teaching purporting that students learn best when their teachers effectively address variance in students' readiness levels, interests, and learning profiles (C. A. Tomlinson, 2001). Tomlinson added that the key goal of DI is to maximize the learning potential of each student. Najiba et al. (2014) proved that the differentiated approach is an effective and exemplary method for improving students' motivation towards learning. Taddesse Melese (2015), citing a number of empirical evidences, explains, "Effective DI involves knowing students, understanding the curriculum, providing multiple pathways to learning, sharing responsibility with students, and taking a flexible and reflective approach." (p. 254). Tomlinson et al. (2003) also stated that "for DI to be successfully implemented in the classroom teachers need to have high motivation and a positive attitude towards practicing the approach since it is daunting and time-consuming." To effectively differentiate in the classroom and to provide education for all, schools must provide teachers with sufficient professional development, collaboration time, and training on specific differentiation strategies to implement in their classrooms.
It is stated that, differentiated instruction can significantly help in revolutionizing educational and teaching practices (Solomon, 2019). This to mean that, the strategy is beneficial for it helps to alleviate the fundamental problems that the teaching-learning process has. Some of the benefits listed by these authors are: it takes care of a large group of students with different abilities; student involvement and engagement also increase as they get to work in their comfort zone, and students get more opportunities and can utilize their potential and abilities in a better way, and it is an effective and exemplary method in improving students' motivation and an increase in students' achievement.
On the other hand, despite the success associated with DI, several studies reported some challenges while performing the approach. Teachers continue to struggle with the challenges of students' diversity in a classroom. They mention that "in a large classroom setting, teachers require more time for planning, organizing, and scheduling the students, either to separate them individually or in a group" (Joseph et al., 2013;Solomon Melesse, 2019, 2020. Generally the above and other empirical evidences are showing that many countries are now using DI because of the benefits it has on educational quality. In Ethiopia, for example, it is revealed that the education system has long standing problems associated with limited and inequitable access, lack of quality and relevance, and a continuous decline in quality and standards. Mentioning MoE (2010), Solomon has noted that in formulating the education policy, attempts were made in order to make sure that all children, youngsters, and adults acquire the competencies, skills, values, and attitudes enabling them to participate fully in the social, economic, and political development of Ethiopia. However, a wider gap remains to address the needs and interests of every learner (Solomon Melesse, 2019Melesse, , 2020. The Ethiopian TVET system, as part of the educational system of the country, has also suffered from problems related to relevance and quality (MoE, 2008). Although a lot of efforts have been made to expand TVET institutions and succeed in tackling the problems related to access, it has been found that the mere expansion could not solve the problems of unemployment and low productivity in the economy. Moreover, it has been noted that substantial skill gaps throughout the economy have been observed. Generally, in summarizing the problems related to the TVET system, the TVET system or the programmes, by-and-large, do not address actual competence needs in the economy, with most programmes being of low quality and theory-driven due to resource constraints and a lack of skilled TVET teachers. A sufficient corps of TVET trainers represents one of the obstacles to TVET development in Ethiopia. There is a widely recognized concern over the poor reputation of the teaching profession, and this thought negatively affects the professional motivation of TVET teachers and instructors and the quality of their profession. The document also stated that most TVET teachers/instructors have relatively low formal qualifications, severely affecting TVET delivery at higher qualification levels. There has been no appropriately and practically skilled and competent manpower to provide TVET with the necessary service in accordance with the occupational standards. This is the result of a training system that has long emphasized theoretical knowledge (Tadesse et al., 2022;Tomlinson & Imbeau, 2010). Generally, according to this report the shortage of a sufficient corps of TVET trainers on hand and the poor quality of them on the other has suffered as a result of the low reputation of their profession.
To improve the pervasive problems of the sector, the government had revised the TVET strategy and had come up with the then new strategy by (MoE, 2008. In this strategy, different measures were taken to alleviate the above-mentioned and other problems of the sector. The introduction of occupational standards to replace the then curriculum-centered approach, the establishment of an occupational assessment system and the improvement of the quantity and quality of TVET trainers were some of the areas that were given emphasis. Despite these and other improvements, quality and relevance remain critical aspects of the sector (Tadesse et al., 2022;MOE, 2010).
The lived experience of the researchers in the regional education and training in general and the long years of experience of one of the researchers in the TVET sector as a teacher in TVET colleges, expert in competency assessment center, a director in the regional TVET bureau and now as college dean in one of the private TVET colleges in Bahir Dar, enables to better understand the problems related to the quality of the training in the sector. The researcher remembers the problems related to the quality of TVET training was a common issue raised in the performance evaluation of the sector at regional level. Following this performance evaluation, short term and long term capacity building programs, have been in place throughout the region. Most of these capacity building programs focus on the teaching methodology and skill upgrading.
These capacity building programs were also in line with the direction given at federal level. It is stated that "to strengthen the role of the TVET system in becoming an agent in technology transfer and to improve the problems entangled with it as well as the TVET trainers competency, as clearly stated in the program action plan of ESDP V drafted to be implemented from 2015/6 up to 2020/21, the government has promised to update and upgrade the TVET trainers. Moreover, the action plan stated "existing institution and industry trainers will be provided with a capacity development programme to upgrade their skills, particularly in relation to technology adaptation' (Taddesse Melese, 2015, p. 97). It was also promised that, the role of TVET management and administrative staff and experts of the Federal TVET agency, regional TVET bureaus/agencies/ commissions, CoCs and TVET institutes will receive a package of in-service training on modern management techniques.
Generally, together with other measures to maintain the quality of education, the researchers strongly believed and want to argue that effective and efficient implementation of DI in the TVET institution or system guarantees the success of most of the goals it envisages. This necessitates the need to check the understanding and implementation status of DI in these TVET institutions.
On the other hand, as far as the researchers' knowledge of the issue is concerned, little or no studies have been conducted on this issue. This necessitates a comprehensive and detail exploration of the case.
Hence, the objective of this study was to examine the theory-practice gap in implementing instructional differentiation in the Ethiopian TVET system. It was also necessary to identify the level of understanding and the extent of practice and see where the gap lay for recommending appropriate intervention.

Research questions
The research was geared towards giving answer to the following specific research questions: • Does the TVET system give recognition to the principles of DI?
• What is the level of understanding of TVET institutions towards DI?
• What is the status of the practical implementation of DI in TVET institutions?
• Are TVET teachers familiar with the strategies of DI?
• Is there any difference among TVET teachers in their understanding and practice of DI as a function?
• Is there a difference among different TVET colleges, as well as public vs. private TVET colleges, in understanding and implementing DI?
• Is there any difference among different educational institutes of teachers in understanding and implementing DI?

Objectives of the study
The objective of this study was to examine the theory-practice gap in implementing instructional differentiation in the Ethiopian TVET system. It was also necessary to identify the level of understanding and the extent of practice and see where the gap lay for recommending appropriate intervention.

Significance of the study
Institutions have to provide students with a favorable learning environment depending on their interests, background, and other differences. They have to be community properties, which should accommodate the different groups of learners so that they can develop to their maximum potential. For the purpose, a lot of empirical evidence has recommended that differentiation of instruction is one of the best strategies to be implemented. Differentiation in a classroom shows that everyone can learn in his/her own particular way despite any learning style differences (Tomlinson, 2003). As both teachers and students learn to work together with these differences within the classroom, a more productive and engaging learning environment should be created. To this end, the theoretical and practical status of the strategy has to be understood and gaps between theory and practice have to be identified.
Hence, this study tried to search for the theory-practice gap in implementing this strategy. Effective completion of the research will benefit the sector and specifically the participating institutions to understand the status of DI and identify where the problem lies. Hence, they could plan to correct the situation. Moreover, the study could also serve as a basis for further exploration of the matter in detail.

Delimitation and limitation of the study
The main purpose of this study was to examine the theory-practice gap in implementing instructional differentiation in the Ethiopian TVET system. Time and finance barriers as well as the current instability of the region as well as the country forced the researchers to delimit the study to institutions found in the Bahir Dar Administrative Zone. It could have been better had the researchers included representative areas at national level to imply support for the sector.
One of the study's potential limitations was the lack of prior empirical evidence on the sector. Another limitation of the study was with regard to the participants and the instruments selected. Another limitation of this study was that data was not collected from various subjects such as the college management body, a representative number of regional TVET bureau officials, and experts. Besides, it would have been better if the researchers had conducted a detailed interview and focus group discussion with some selected teachers and other participants. Moreover, methodologically, since its focus was to see the theory-practice gap, it would have been better if observation had also been included as an important data collection method.

Research approach and design
For the purpose and better understanding of the case, the researchers chose mixed research approach for different reasons. The first reason was that, unlike using either quantitative or qualitative (either single approach alone), the mixed approach allows the researchers to employ multiple methods, different world views, different assumptions, as well as different forms of data collection and analysis. Moreover, the core assumption of this approach, according to Creswell (2014), is that this form of enquiry provides a more complete understanding of the research problem than either single approach alone. Specifically, an embedded mixed design was employed in the study (Creswell, 2012). According to Creswell, this is a method in which the researcher collects quantitative and qualitative data concurrently or sequentially, but with one form of data supporting the other. Hence, the researchers collected both forms of data at the same time and integrated the information in the interpretation of the overall results.

Population, sample size and sampling techniques
The study's population included regional TVED bureau trainers' capacity development case experts, college deans, trainers, and trainees currently enrolled and taking training. According to Bahir Dar City Administrator TVED Office, there are two public and seven private TVET colleges.
The researchers employed both purposive and random sampling methods to get a representative sample of the population. From the seven PTVETC, three colleges were included in the sample. These colleges were selected randomly using a lottery system, and the two public TVET colleges, namely Bahir Dar Poly Technique College and Bahir Dar Health College, were included in the study purposefully to see them because they are organized under different regional offices. The former is under the Amhara Regional State TVED Bureau while the latter is under the Health Bureau.
In all colleges, the deans/vice deans, the colleges' research and quality assurance office focal persons, and trainers were included as participants in the study, and individual sample respondents were selected using different sampling techniques. Table 1 shows the population of the study, sample size, and sampling techniques employed in this study.. Table 2 discloses how the sample size in this study was decided. It was also noted here that an attempt was made to select samples keeping a reasonable representation of males and females as detailed in the table.

Data collection instruments
The researcher used a variety of ways to obtain the information needed for the investigation, depending on the design chosen. As a result, the questionnaire, focus group discussion, and document analysis were used to collect data for the study.

Questionnaire
To gain sufficient and reliable primary data, the researcher used a questionnaire as the primary data collection instrument. Carol Ann Tomlinson, a well-known educator and researcher, designed and used the teacher self-assessment format, and Sandra Page revised and used the modified format for teacher self-assessment. The one employed in this study, on the other hand, came from two other researchers (Taddesse, 2015) who had used the tool in various forms for the same purpose.
To check and improve the validity and reliability of the instrument, different techniques were employed. As a result, the researchers gathered comments from one instructor and PHD candidate in Bahir Dar University and another research and community unit coordinator in one private college in Bahir Dar, who provided valuable comments that could maximize the face validity of the instrument. Then, before the instrument was employed for the final purpose, it had been pilot tested in one private TVET college named "ALKAN" with four teacher respondents. After the pilot survey, in addition to the readjustment on some of the items and formats, the original tool created by Ann (2012) and Taddesse Melese (2015) which was a four point scale tool was modified to a five-point Likert scale instrument. The reliability and internal consistency were assessed using Cronbach's Coefficient Alpha (Cohen et al., 2007), and the reliability coefficient (Cronbach alpha) was calculated and found to be 0.895.
Generally, the questionnaire contains items that are used to assess teachers' understanding of DI, implementation status, their frequency of use of different instructional strategies for DI, factors helping teachers in the implementation of DI, and factors hindering teachers in implementing differentiated instruction.
The questionnaire was pilot tested at one private TVET college before being utilized for the final data collection purpose. Two more researchers made minor adjustments when the pilot was completed. A four-point likert scale was the original tool, as well as the one utilized by the above researchers. The tool used in this study was updated to a five-point Likert scale after the pilot test and discussions with academic colleagues at Bahir Dar University.
In general, the questionnaire covers items that measure teachers' awareness of differentiated instruction, implementation status, and frequency of use of different instructional strategies for DI, factors that help teachers implement DI and factors that inhibit teachers from implementing DI.

Interviews
Semi-structured interviews in the form of conversation were conducted with regional TVED authorities and specialists, college quality focal individuals, and trainers. These individuals were interviewed in order to gain a better grasp of DI knowledge and practice, as well as the broad aspects that help or impede DI implementation.

Document review
The researchers examined the selected TVET curriculum, TTLM materials, and the training manual used in the system for the training to further investigate and triangulate the case.

Reliability test of variables
According to Orodho (2009), validity relates to how correctly an instrument portrays the information it is supposed to measure. As a result, the researchers asked specialists for input on the instrument in order to increase its validity. The initial draft tool was sent to one PhD candidate in another school and one expert in the field, who provided valuable comments. Another way utilized to increase the instrument's reliability was pilot testing. The original tool created by Ann (2012) and Taddesse (2015) was employed in one of the sample TVET colleges named ALKAN with four respondents. After the pilot survey, the four-point Likert scale tool was replaced with a five-point Likert scale instrument. The reliability and internal consistency were assessed using Cronbach's Coefficient Alpha (Cohen et al., 2007), and the reliability coefficient (Cronbach alpha) was calculated and found to be.895.

Methods of data analysis
Both quantitative and qualitative data analysis techniques were employed. The known techniques for quantitative approach such as percentage, mean, standard deviation, one sample t-test, independent samples t-test and one way ANOVA were employed.
One sample t-test was used to see the knowledge of the TVET institutions' instructors in practicing DI. Whereas, independent sample t-test was used to see gender, qualification and college type difference in the knowledge and practice of differentiated instruction. One-way ANOVA was employed to see the effects of TVET teachers' academic status and college type towards the understanding and practice of DI. For the overall analysis of both descriptive and inferential statics, this study used the latest and new version of SPSS 21.
Moreover, the degree of understanding and practice of the subjects was treated against the recommendations made in the review as well as the national policy directions.

Results and discussion
This chapter presents the major findings of the study in line with the major research questions proposed. These are followed by discussions of the study's major findings in relation to previous research findings and a review of related literature.

Does the TVET system recognize the theories and principles of DI?
It was the intention of this study to know whether or not the TVET system at the very beginning recognized the theory and principles of DI, whether or not the TVET system believed that DI was beneficial to the system, and if that was true, in what way the system recognized DI.
For this reason, a dialogue was held in the form of a free and flexible manner with the ANRS TVED bureau education and training directorate and one higher expert in curriculum implementation. The researchers began the conversation with them by asking if they were familiar with the term "differentiated instruction". This was the first question raised by the researchers at each college prior to the distribution of the questionnaire and even before the talk began. The researchers discovered the first clear message was that no one had heard of the term. As a result, the researchers had to clarify the definition and notion of the phrase in every conversation and interview before moving on to the next topic. Surprisingly, it was found that they were familiar with the concept and practice. This implied that they were new to the term but not to the concept or practice of DI.
In further discussion, it was found that the system was seemingly cognizant of the benefits of the principles and the theory behind DI and had actually recognized the principles of DI. They stated that the strategy, the curriculum, and the Teachers' Training and Learning Materials (TTLM) prepared had substances related to the principles, and the system was ideal for the theory and principle of DI. They argued that the problem might have been in putting this into practice for different reasons. In the document analysis, the researchers also referred to the 2008 TVET strategy, curriculum, and TTLM of some occupations. In the 2008 TVET strategy, it was stated that providing high quality, relevant technical and vocational education and training to all citizens to create a competent, motivated, adaptable, and innovative work force was considered as an objective of the strategy. Moreover, in its strategic points, it was clearly stated that creating a conducive learning environment for females and people with special needs, developing a multiculturally responsive curriculum and other training materials in the TVET system, designing and implementing inclusive TVET programs for vulnerable, disadvantaged, and disabled trainees, and establishing resource centers for trainees with special needs in all TVET institutions were some of the strategic points mentioned to be focused on in the revised TVET strategy. In addition, relevance and quality, access and equity, and inclusiveness were some of the guiding principles boldly written in this revised strategy. Hence, from this, one could easily infer that the reformed TVET strategy gave due attention to the principles of DI to meet its objectives.
Furthermore, the TVET system's Teacher's Guide, which is one of the TTLM components, is written following some DI principles. According to the teacher's handbook established for the occupation of Masonry level II (Taddesse Melese, 2015) evaluated for this purpose, teachers must follow the system's design and mechanics of training. "Teachers must emphasize the importance of providing training that follows the independent learning approach, which allows trainees to be masters of their own environment and in charge of their learning," according to the guidelines. "Teachers must emphasize the importance of using a variety of teaching methods, the importance of module-based assessment, and the need to check students' readiness before examining institutional assessment." In addition, formative and summative evaluation systems designed for assessing students' development were devised. In its formative evaluation, the "progress chart" was utilized to track students' development. Only those students who scored satisfactorily in each learning outcome and module were forwarded to the next module. Others who failed would be given at most two more opportunities to be trained and retested. During the conversation, it was learned that the system had also implemented an external assessment system, which required students to demonstrate competency before progressing to the next level. All of these concepts were based on DI principles. As a result, it is possible to generalize that the Ethiopian TVET system, which appears to be aware of the benefits of DI, incorporated concepts related to this in its system documents.
With regard to what gaps were clearly existed, the term was not familiar with the system. Actually, solutions to our educational problems do not lie in the naming. What is more important is engaging in the practice. The findings of C.A. Tomlinson (2008) were inconsistent with this. After observing a number of teachers, classrooms, and schools, they assume that they have started to implement DI, but actually have not. This implies that solutions to educational problems do not lie in names or in labels but in quality practice; calling something "differentiation" provides no guarantee of its efficacy for students.
However, the fact that the phrase is not well understood by officials and even by system papers may prevent the system from properly comprehending the DI concept and executing it in its entirety. In this regard, Stavroula, Valiande, Leonidas, and Mary (2011) argue that, while many curriculum reforms and policies were developed with the goal of providing and promoting equity through the improvement of educational quality, the results of such efforts around the world have not been promising. The authors mentioning Valiandes et al. (2011) argued that traditional and undifferentiated instructional approaches and practices that do not facilitate the construction of knowledge for all students in mixed ability classrooms are seen as one of the basic factors causing this problem.

The understandings and implementations of differentiated instruction and the frequency of utilizing DI strategies in their classrooms-by the main implementers-Teachers/Trainers
TVET trainers were questioned about their exposure to or training in general teaching methodology and specifically differentiated instruction in this regard. According to the findings, 171 (86.8%) TVET trainers have taken teaching/training methods and 165 (81.6%) were aware with DI concepts. This could indicate that these trainers have an excellent understanding of DI. This does not, however, indicate that trainers are aware of how to differentiate instruction. The fact that the majorities of trainers have received general methodology training and have a good understanding of DI creates a conducive environment for DI implementation. Ann (2012) came to the same conclusion. He discovered that the general average for comprehending differentiated instruction for K-6 teachers was 92.12.
On the other hand, Taddesse Melese (2015), mentioning a number of empirical findings such as Scott (2012), has revealed that their findings are in contrast to this one. For example, Scott (2012) revealed that there has been a lack of deep awareness of how to fully implement it.
As shown in the table 3 above, the obtained mean (3.81) is greater than the expected mean (2.5). This reveals that TVET trainers' understanding/conception of DI is high (t = 32.743, p < 0.05). In this study area, about 81.6% of TVET college teachers responded that they took training on DI and, as a result, they had a better understanding.
The fact that the result is in contrast with many findings conducted on general education teachers as depicted by Taddesse Melese (2015) and other findings such as mentioned by Taddesse might be due to the nature of education of the sector and the emphasis given to the sector as a result of the reform as mentioned earlier.
On the other hand, there are also findings, even in general education teachers that have scored a high degree of understanding towards DI. For example, in studying the effects of differentiated instruction in the science classroom, the results have shown that the majority of the teachers (73%) involved in the survey believed that the use of DI in their classroom made them better teachers and also helped the students' confidence level. Similarly, Scott (2012) has found that the overall mean for understanding the concepts of differentiated instruction for general education teachers was 91.83 (sd = 9.31) and a median of 94.00, and the mean score for special education teachers was 96.15 (sd = 6.17) and a median of 97.50.
But it should also be noted that though a high conception towards DI was found, the results from the interview as well as document analysis of the training methodology material revealed that detailed training on the mechanics and strategies of DI was not given.
Furthermore, TVET college trainers were asked about their familiarity with the instructional strategies of DI and the analysis is given below (Figure 1).
As previously stated, the majority of TVET teachers noted that they were unfamiliar with most of the DI instructional tactics and so failed to execute them. Similarly, only 23.9 percent of TVET college trainers stated that they used curriculum compacting as one of the eleven DI tactics. Flexible groupings and pre-assessment data were both acquainted to the remaining 17.3 percent and 15.7 percent of TVET college trainers, respectively.
TVET teachers reported that the least used strategies in their classroom practices were independent study/work, varied instructional materials, tired assignments, and learning contacts.
The result of this study, in general, showed that the majority of the TVET college trainers were not familiar with various strategies of DI, which might have adverse effects on implementing those strategies in the actual classrooms.
Teachers who tried using strategies of differentiation without enough training were found lacking the skills to employ the different techniques of DI effectively. This may make it difficult to improve students' achievement and address students' special educational needs.
In relation to this, Koezye (2007), as mentioned by Taddesse Melese (2015), failed to frame students' learning choices, learning styles, interests, and learning preferences in the classroom.
Though the majority of TVET college trainers were less familiar with the strategies of differentiation, in terms of practice, some trainers exercised some strategies (like use of curriculum compacting, flexible groupings, pre-assessment, students' choice) better than the other strategies (interest groups/centers (10.7%), varying questions (9.6%), and learning centers/ groups (8.7%).
In contrast to this finding, Rodriguez (2012) found that out of the eleven DI tactics she utilized, 87 percent of teacher respondents were familiar with flexible grouping and 86 percent with autonomous projects or investigations (Taddesse Melese, 2015). Taddesse, on the other hand, found that the independent study was the most common instructional technique in his research, while it was one of the most common in the current study, too.
Furthermore, Taddesse discovered that pre-assessment, learning centers, and curriculum compacting are among the least used instructional techniques, although curriculum compacting and pre-assessment are among the most widely used strategies in this study.

The frequency of use of instructional/management strategies of DI
Here, though, generally, it was found that the familiarity of the strategies was found to be unsatisfactory. In this part, it was tried to check how frequently TVET college teachers were applying different strategies of differentiated instruction.

Figure 1. Familiarity of TVET trainers on instructional strategies of DI (N = 197)
It was found that curriculum compacting was the most frequently employed strategy. But surprisingly, this strategy was one of the least frequently used in a study conducted by Taddesse Melese (2015) and even in the findings of other researchers like Rodriguez (2012). This may be due to the flexible nature of the TVET curriculum. As it is mentioned in the 2008 reformed TVET strategy, one major area of reform was the curriculum, with flexibility being one characteristic of it. This may be due to the fact that, in the TVET system, there are specific standards in each occupation identified to be met by every student and, hence, students' choice may be overlooked.
(1) Differences in TVET College Trainers' Practices of the Overall DI as a Function of Demographic Variables The overall practice of DI was compared based on gender (male teachers and female teachers) using Independent Samples t-test and a significant difference was observed (t = 2.092, p < 0.05 at df = 195). As a result, as compared to male trainers (mean = 3.73), female trainers (mean = 3.55) were found to practice DI less. Table 5 shows the mean difference in Differentiated instruction practice for males and females. The difference is very small in favor of males. This finding was supported by the research findings of Scott's (2012) study. The study indicated that there was a slight decrease in female test scores from before to after treatment in mathematics. Male students' performance increased by 4.09% after differentiated instructional strategies was implemented in mathematics instruction. But the findings of this study were against the study findings of Taddesse Melese (2015), where the mean for females was greater than for males. Though more research is needed, the difference in results could be due to the fact that most TVET requires practical hands-on training that may also require physical fitness due to the nature of the training.

Differences in TVET college trainers' practices of the overall di as function of qualification
Comparisons were also made to see how trainers' qualifications affect their ability to apply DI concepts. An independent samples t-test was used to compare the three distinct qualifications (Diploma VS Degree, and Diploma VS Master's), as shown in Tables 6 and 7 below.
In terms of the overall DI practice, a significant difference was noticed (t = 4.902, p 0.05 at df = 95) when comparing Degree and Diploma TVET college trainers using Independent Samples t-test as indicated in Table 4 That is to say, the mean value of Degree holders (3.69) differs significantly from the mean value of Diploma holders (4.33). Despite the fact that considerable discrepancies in qualifications were identified, Koeze (2007) found that trainers who participated in the DI program reported frequent differentiation in the areas of readiness, interest, flexible grouping, choice, and learning styles.
Similarly, a significant difference was discovered (t = 6.654, p 0.05 at df = 119) in the general practice of DI as comparisons done between Master's and Diploma TVET college trainers using Independent Samples t-test as indicated in Table 7. That is, the mean value of Master's Degree holders (3.54) is significantly different from the mean value of Diploma holders (4.33).
However, as the overall practice of DI comparison made between Masters and Degree holder TVET college trainers using Independent Samples t-test in Table 8 reveals, significant difference was not observed (t = 1.893, p < 0.05 at df = 174). That is, the mean value of Master's Degree holders (3.54) is significantly different from the mean value of Degree holders (3.69).
As shown in the above three tables, a significant mean value difference was observed between Diploma holders and other trainers, whereas the mean value difference between Degree and Master's Degree holders was found to be insignificant. This finding is unexpected and could be against a lot of previous findings. For example, Taddesse Melese (2015) did not find a significant difference between the mean value of Degree holders (128.39) and the mean value of Diploma holders (126.49). The fact that Diploma holder TVET teachers' mean value is greater than that of Degree and Master's Degree holders' is interesting and could be reasoned out in two ways. On the one hand, these groups of TVET teachers are products of the TVET institutions themselves. There is no other institution which is giving training at this level. Hence, the experience they acquired in their stay as students as well as teachers in the system might have helped them in understanding the strategy and hence in performing better. On the other hand, these trainers are supposed to teach mostly the practical aspects of the training. For instance, in health colleges, these trainers are laboratory assistants who are supposed to train the practical training. The same is also true in other occupations. Table 10 shown below also summarizes the same result.

Differences in TVET College Trainers' Practices of the Overall DI as a Function of College Type
Comparison of the mean values of the overall implementation of DI among TVET college teachers based on their college type where they were working/ teaching/ was made using One-way ANOVA (F, 192) = 1.002, p > 0.05). As shown in Table 9, the finding revealed that significant difference was not observed among the different TVET colleges.
The fact that there was no significance difference even between and among the public and private TVET colleges revealed that the gap related to DI was systemic and needed solution at regional or higher levels.

Differences in TVET College trainers' implementation of elements of DI as a function of demographic variables
According to C. A. Tomlinson (2001), since the key goal of DI is to finally maximize the learning potential of each student, the key implementers need to practice it as recommended by the famous scholars of the principle. Hence, beyond the understanding of the principles of DI, trainers need to practice and implement it so that students could benefit. For the classroom implementation of the principles, Tomlinson and Imbeau (2010) has identified six areas as components/ elements of differentiated instruction namely student interest, assessment, lesson planning, content, process, and product where differentiation is put into practice.
In relation to this, TVET trainers were asked to check their practical implementation status of these components. The following table shows the result of the independent sample t-test of the elements of DI by TVET college trainers as a function of demographic variables.
As shown in Table 11, a statistically significant difference was observed between male and female TVET college trainers in some of the components, such as assessment, process, and product, whereas there was no significant difference between males and females in the rest three components. From the table, it is shown that for the component "assessment", it is found that the mean value of male TVET trainers (3.77) was greater than that of female (3.51) at (t = 2.105, p 0.05 at df = 195) Table 12.  Similarly, it is also found that the mean value of male TVET trainers (3.73) is greater than that of females' (3.45) at (t = 2.495, p 0.05 at df = 195) for "process" and the mean value of male TVET trainers (4.01) is greater than that of female trainers (3.81) at (t = 2.211, p 0.05 at df = 195) for the component "product". And the difference is found to be significant. Table 13 discloses the status of supportive factors for the implementation of DI. Readers can easily see the contribution of each factor by reading the percentage of contribution of each factor put to DI implementation.
However, a significant difference was not detected in terms of student or trainee interest, session planning, and content. A similar study conducted on primary teachers here in Amhara at primary teachers by Taddesse Melese (2015) has found that only "product" has been found to have a significant difference, the mean value of females being greater than that of males. This result is against the findings of the current study, where males scored better than females.
On the other hand, males scored the highest mean value (4.01) in the area of' product,' while females scored the lowest mean value (3.28) in the area of "student interest." Neo (2012) discovered that the component "product" is one of the least implemented components of differentiated instruction, while content is the most implemented component. The fact that males scored higher than girls could be explained by the nature of TVET education and training, which emphasizes on practical skills.
Generally, it is found that TVET trainers' understanding of the principles of DI was better than their implementation. Hence, it would be straight forward to give attention to all of the components of DI to maximize the benefit of students (Tomlinson & Imbeau, 2010).

Factors helping TVET Trainers in the implementation of DI
TVET trainers were also asked to identify factors that could have helped them in the implementation of DI in their institutions. Participants were provided with eleven factors that are found to have similar effect at different intensity.
As shown in the table below, school administration and leadership support were among the top characteristics cited as crucial to facilitating DI implementation, with 74.1 percent of TVET college trainer respondents (n = 146) identifying them. The second key facilitating element recognized by 72.1 percent (n = 142) of the trainers was commitment and experience, and the third key component indicated by 68 percent (n = 134) of the teachers was knowledge and experience. Taddesse Melese (2015) discovered that the initial top three elements supporting DI implementation are knowledge and experience (93.53), commitment and motivation (86.20), and availability of materials and resources (71.98). Table 14 disclosed some basic factors hindering TVET trainers to implement differentiated instruction.  Small class sizes, planning time, availability, and student diversity were shown to be the least identified criteria. The fact that time availability is the third least essential element contradicts Taddesse Melese's (2015).
Another significant result is the importance of collaborating with other staff members when implementing DI. In the case of TVET education and training, this is a critical factor. One academic dean in the conversation confirmed that other staff's participation is critical for the DI to be implemented effectively. This result contradicts Taddesse's findings once more (Taddesse Melese, 2015).

Preventing/Hindering factors for the implementation of DI (N = 197)
Although there is evidence to support the benefits of DI, it is difficult to put into practice. In relation to this, participants were asked to rate the barriers to DI implementation in the same way that they rate the supporting elements. The amount of preparation time on how to differentiate instruction was cited as the first impeding issue by 161 (81.7 percent) trainers, as shown in the table below. Taddesse Melese (2015) and Rojo (2013) disclosed similar conclusions.
According to Rojo (2013), time is a big challenge in applying DI for the majority of participants. "The greatest problem in my classroom while using DI during this past school year was being able to cover all of the needed content of the course material at the rate mandated by the school district," one research participant said. The current study showed similar reflection in the discussion with some of the participating institutions' deans. The shortage of materials and resources, big class size, lack of school administration support, and lack of parental support were cited as the second and third significant factors by 150 (76.1%), 145 (73.6%), 142 (72.1%), and 128 (65%) respondents respectively.
On the other hand, range of diversity in class room (62.9%), lack of knowledge and experience (61.4%), %), lack of staff collaboration (60.4%), shortage of time (56.9%), traditional outlook of one size-fits for all (55.3%), engaging on routine tasks (55.3%) and lack of commitment (43.7%) were factors identified to prevent the success of the implementation of DI.

Conclusions
On the basis of the findings and the discussions made, the following major conclusions could be drawn: One of the result of the study showed that the understanding of DI by TVET college teachers was high even though its implementation was low. The majority of TVET trainers were not found to be familiar with the different instructional strategies of DI; in terms of practice, however, some teachers were found to implement some strategies infrequently and irregularly.
Despite the fact that the overall status and implementation of DI by TVET trainers was low, comparisons on gender indicated that male trainers practiced DI better than female trainers. Similarly, Diploma holders were found to have practiced DI better than Degree and Master's holders. However, college type and trainers' experiences did not indicate a statistically significant difference.
School administration support, commitment, and experience, as well as knowledge and experience, are among the critical factors that support the implementation of DI, whereas the availability of time, range of student diversity, and small class size have minimal effect in supporting the implementation of DI.
On the other hand, the amount of planning time, a lack of materials, and a large class size were discovered to have a greater impact on the implementation of DI. Moreover traditional outlook of one size fits all, engaging in routine tasks and lack of commitment are factors that have minimal effect in hindering the implementation of DI.
It could also be concluded that there is a clear gap between the theory and actual practice in relation to DI in the TVET colleges studied.

Recommendations
Based on the findings and conclusions of this study, the researchers made the following recommendations that would contribute towards improving the practice of differentiated instruction in the TVET colleges: Training and discussion programs should be arranged to create awareness amongst the regional TVED bureau leaders and experts, TVET colleges' deans and instructors about the meaning, importance and findings of this study. This could motivate them to engage in measures that could change the situation.
The policy and strategy principles and concepts of the Ethiopian TVET system in line with the principles of DI should be precisely communicated up to the bottom of implementers. This would help them to understand that the principles of DI is not totally out of the policy direction of the system which further helps to put the concepts in to practice.
The training materials for teaching methodology of TVET trainers should be improved by incorporating the theories and principles of DI and other contemporary pedagogies that could serve the system best. Based on this improved training material, a capacity building program should be designed and executed both for TVET managers and trainers.
A reward system based on performance assessment system should incorporate the practice of DI hence staff may get motivated to implement it.
Finally, detail studies on the practice of the theory and principles of DI and other studies that focus on the quality of TVET training should be studied and interventions that could improve the case should be devised.