Publisher: Encyclopedia of Education, 2nd Edition
Page Numbers: 2542-2545

The impact of test preparation programs is a very controversial topic. The controversy hinges in large part upon how program impacts are quantified. Students taking commercial programs are usually given some sort of pre-test, a period of preparatory training, and then a post-test. The companies supplying these services will typically quantify impact in terms of average score gains for students from pre to post. Conversely, most research on the subject of test preparation will quantify impact as the average gain of students in the program relative to the average gain of a comparable group of students not in the program. Here the impact of a test preparation program is equal to its estimated causal effect. The latter definition of impact is the more valid one when the aim is to evaluate the costs and benefits of a test preparation program. Program benefits should always be expressed relative to the outcome a person could expect had they chosen not to participate in the program. This review takes the approach that program impact can only be assessed by estimating program effects.