In this study we aimed to analyse the effects of the Instructional Curriculum based on Cooperative Learning (ICBCL) prepared for the subjects, the orders of electrons and chemical properties, chemical bonds, compounds and their formulas, and mixtures on 7th grade learners' learning achievements, motivations to learn science, and their attitudes towards learning science. Pre- and post-test quasi experimental design was used in this study in which the participants, 89 7th grade learners were attending a public secondary school in Istanbul, Turkey during the 2013-2014 academic year. The Diagnostic Test for the Structure of Matter and its Properties (DTSMP), developed by the researchers, the Motivation Scale to Learning Science (MSTLS), developed by Dede and Yaman (2008), and the Attitude Scale Towards Science Lesson (ASTSL), developed by Biçer (2011) were used as data collection instruments. SPSS 16 and Lertap 5 were used for data analysis. As a result of the post-tests, learners from the experimental group achieved significantly higher mean scores than learners from the control group. This reflected that ICBCL was highly effective on increasing learners' achievement levels by preventing possible misconceptions, developing motivation, and positive attitudes compared to the current Science Teaching Curriculum (STC).