Validity and practicality of guided discovery learning models for chemistry learning in senior high school

This paper is part of a dissertation study that aims to reveal the level of validity and practicality of guided discovery learning (GDL) model developed for senior high school chemistry learning. This research and development study used 4D instructional design model. Instruments used were observation sheets and questionnaires. The product was validated by 12 experts and tested on 8 chemistry teachers and 96 students in three public senior high schools in Padang, Indonesia in 2016/2017 academic year. Observation results were analyzed by percentage technique while data of validity and practicality of GDL-PK model were analyzed with Cohen's kappa formula. Analysis showed that the average values of kappa moment (k) were 0.87 for validity test and 0.91 for practicality test belonging to very high degree category. Analysis of observation result showed that the average percentages of model implementation were 94% in SMAN X Padang, 97% in SMAN Y Padang, and 87% in SMAN Z Padang having very high degree category. Results showed that GDL-PK model was valid and practical and could be fully implemented by teachers and students in chemistry learning. Therefore, the developed GDL-PK model was feasible as teachers' and prospective teachers' considerations for senior high school chemistry learning.