5.1 Improving students’ long-term knowledge retention. Can a technique known as personalized review improve students’ ability to remember material learned in a course? To answer this question, a researcher recruited 200 eighth-grade students who were taking introductory Spanish. She assigned 100 students to a class training students to use the personalized review technique as part of their study habits. The other 100 continued to use their usual study habits. The researcher examined both groups on Spanish vocabulary four weeks after the school year ended. Outline the design of this study using a diagram like Figures 5.2 and 5.3.