Although it is difficult to determine from the TIMSS data exactly how much time is spent on lecturing as distinct from problem-solving activities, it appears that teachers generally follow the advice given by progressive educators. On average, they allocate twice as much time to problem-solving activities as to direct instruction. Specifically, teachers devote about 40 percent of class time to problem-solving activities (with or without teacher guidance); during roughly 20 percent of class time, students listen to the initial presentation of material to be learned. The remainder of the class time is allocated to such tasks as class management, reviewing homework, re-teaching the material, and clarifying content (see Figure 1).