We have investigated the effects of a teaching intervention based on evidence from educational theories and research data, on students' ideas in chemical kinetics. A quasi-experimental design was used to compare the outcomes for the intervention. The subjects of the study were 83 university first-year students, who were in two different classes in a 4-year pre-service science teacher-training programme in Turkey. During teaching, an "evidence-informed instruction" was applied in the experimental group whereas "traditional instruction" was followed in the control group. Students' understandings of chemical kinetics were elicited through a series of written tasks and individual interviews. The results showed that while there was no significant difference in students' understandings in chemical kinetics in the two groups on the pre-test, in the post-test the students in the experimental group achieved significantly higher learning gains in chemical kinetics than did the students in the control group. Moreover, in response to teaching, students in the experimental group were more likely to use their knowledge consistently across different contexts (average 63.1%) than students in the control group (average 19%). The significance of these findings for further research, and for policy and practice relating to science teaching, are discussed. (Contains 7 tables and 2 figures.)