The main goal of this study is to present a sample lesson plan on acids and bases based on Science, Technology, Engineering and Mathematic (STEM) education for Turkish Science Education System. Determining the impact of instructional materials on learning outcomes of children as a pilot study before the main implementation is also another goal. Single group pre-test/post-test design was used in the study. 12 different 8th grade students were chosen for the population of the study. The instructional materials within the STEM education were organized in accordance with 5E learning cycle model in order to teach the subject to children. Primarily, in order to determine students’ knowledge on the subject, a survey of 10 open-ended questions were presented to the students. After determining their learning outcomes with teaching interventions, the same questions were restructured. Wilcoxon Signed Ranks Test for Paired Samples, non-parametric test and Cohen's Kappa test were used to analyze the data with SPSS 20.00 program at .05 significant levels. It was determined that achievement levels of the students on post- test were higher than the pre- test. Herewith, sample lesson plan was found to be quite effective on students’ levels of gaining the learning outcomes.