This study aims to analyze the effect of the Two Stay Two Stray learning model on cognitive learning outcomes for the Diversity of Living Things and Their Conservation Efforts. The research was conducted by using a quasi-experimental method on seventh grade students of SMPN in Serang Regency, Banten Province. The research data were analyzed using statistics of descriptive and t-test inferential. The results showed that the cognitive learning outcomes who were taught using conventional learning models had an average score of 71.7; while for students who used the Two Stay Two Stray learning model obtained an average score of 78.8. The results of inferential analysis obtained t-count = 3.694 higher than t-table = 1.729 so that it can be concluded that there is a significant effect of the Two Stay Two Stray learning model on the cognitive learning outcomes of the Diversity of Living Things and Their Conservation Efforts. In order to improve student cognitive learning outcomes, teachers should use the Two Stay Two Stray model in the learning process in the classroom.

The objective of the study was to know the effects of interaction between formative assessment frequency and learning independence toward Calculus learning outcomes with controlling university students’ prior capacity. Research using experimental methods with 2 x 2 treatment by level design, and can be concluded from the finding, that with controlling university students’ prior capacity:  (1) the  group with high learning independence and was given  formative assessment  each subject matter got lower score on calculus learning outcomes than the group was given conventional formative assessment, (2) the group with low learning independence and was given formative assessment  each subject matter got higher score calculus learning outcomes than the group was given conventional formative assessment, (3) the group was given formative assessment each subject matter and have high learning independence got lower score calculus learning outcomes than the have low learning independence, and (4) the group was given conventional formative assessment and have high learning independence got higher score calculus learning outcomes than the low learning independence. The result showed that there was  interaction between formative assessment frequency and and learning independence toward Calculus learning outcomes with controlling university students’ prior capacity. To improve  the quality of Calculus learning outcomes, the lecturers were supposed to evaluate the university stuents’ using formative assessment variously. It must be matched with level of the learning independence of university students’.