The aim of this article is to assess the efficacy of using similarities and differences as a teaching strategy. The use of similarities and differences includes various sub-strategies, such as comparison and contrast, classification, the creation of analogies and the creation of metaphors. These strategies are said to create an abstract schema related to the object of the lesson, which students can then apply to analogous concepts, thus speeding up the learning process. The authors conduct a meta-analysis of experimental studies on the subject published between 1998 and 2008. The results of the analysis show that the use of similarities and differences has a positive influence on student achievement, confirming previous research. A closer look at the data shows that this positive effect is particularly apparent in comparison to the results achieved by using textbook-guided instruction, while comparisons with other interactive methods of instruction show a less significant difference in effectiveness. This suggests that perhaps what really makes the difference is the teacher’s ability to engage students in the learning process. In any case, the results of the study support the use of analogical reasoning as a teaching strategy.