Abstract:
The aim of this study is to test whether or not the combined effects of Mastery Learning Method of Instruction and Laboratory experiments have an impact on the achievement levels of science students at a secondary school over control conditions as well as deaeasing scientific misconceptions. Three ninth gade classes of a private secondary school in Istanbul were used. The first class was assigned as the Mastery learning with laboratory experiments goup. the second class as the Mastery Learning goup. The third class was divided into two; one division was utilized as the control condition with laboratory experiments, the other half as the control goup. The hypotheses of the study are : Hypothesis 1 ) The science achievement level of the goups under Mastery Learning . Method of instruction will be significantly higher than the control goups. Hypothesis 2) The achievement level of the goups using laboratory experiments will be significantly higher than the control goup. Hypothesis 3) Laboratory experiments will have an additive effect to the Mastery Learning method of instruction. Therefore, the class under the Mastery learning method of instruction combined with laboratory experiments wi" not only score higher than the control goup. but will also have the highest mean scores when compared to the Mastery learning or the goup using laboratay experiments on the summative test. Hypothesis 4) Students in Mastery learning and I or laboratory experiment goups will have a lesser amount of science misconceptions due to their higher achievement levels. Therefore, students of the most successful goup will have the feast amount of science misconceptions. To ·test the frst and the second hypotheses, a one - way analysis of variance. Newman - Keuls formula, and effect size analyses were used. To test the third hypothesis, a two - way analysis of variance and E correlation ratios were utilized. To analyze the fourth hypothesis, a oneway analysis of variance, Newman - Keuls formula, effect size analyses, a· two - way analysis of variance and E correlation ratios were used. Analyses of the data indicated that: 1 0 Mastery learning and laboratory experiments have strong effects on summative achievement. But the effect of Mastery learning is much stronger than that of laboratory experiments. 2. The Mastery leaning with laba-atay experiments goup achiev~ highest on the summative test ,followed by the Mastery learning. followed by the control with laboratay experiments. followed by the control goup. 3. The impact of laboratory experiments is geater under control conditions in comparison to Mastery learning conditions. 4. The effect of Mastery learning and laboratory experiments is additive and geater than the single effect of either alone. 5 The effect of Mastery learning seems strong in decreasing the amount of science misconceptions, while laboratory experiments have no siglificant effect in preventing the occurrence of these type of misconceptions. The findings indicate that Mastery learning which is able to increase achievement levels of students to one standard deviation over the control conditions, raises science achievement levels to 4 standard deviations over control conditions when utilized with laboratory experiments. Although these two interventions increase achievement levels, only Mastery learning increases the probability of correct conceptualization, but this effect is not as strong on . the misconception test (DEMIT) as it is on the summative test.
