The effects of differentiated instructional design on students? self-efficacy beliefs, metacognitive skills and academic achievement

In recent years it became more important to make students, who have different charactheristics in various areas, develop some basic skills. Especially, basic mathematics skills are required for all persons, who want to solve his/her real life problems effectively. Therefore,in mathematics education, it is necessary to reach all students in the classroom. This study focuses on differentiated instructional design, which provides different ways to reach all students with varied characteristics in a learning environment.Differentiated instructional design in the center, the research aims to investigate the effect of these design, to metacognitive skills and self efficacy of students. The research design is pretest-postest design. The treatment group consists of 25 sixth grade students, who are attending Esenler Cumhuriyet Primary School. Achievement test, self efficacy scale and metacognitive skills scale are developed by the researcher and specialists, and implemented twice, before and after treatment. All instruments? reliability and validity analyses are done.The results of the study supported the first hypthoses stated as ?the postest achivement scores of the treatment group are significantly higher than the pretest scores.? There are also significant differences favoring the postest, in knowledge, comprehension and application questions of the achievement tests. The second hypotheses stated as ?the postest metacognitive skills scores of the treatment group are significantly higher than pretest scores? and the third hyptoheses stated as ? the postest self efficacy scores of treatment group are significantly higher than pretest scores? are also supported by the results of the study.The results are interpreted and suggestions are developed for teachers and researchers.