<P> John Hattie's Visible Learning: A Synthesis of Over 800 Meta - Analyses Relating to Achievement (2009) summarizes the results of four meta - analyses that examined Direct Instruction . These analyses incorporated 304 studies of over 42,000 students . Across all of these students, the average effect size was . 59 and was significantly larger than those of any other curriculum Hattie studied . </P> <P> Direct Instruction is recognized as one of two effective models of comprehensive school reform and, in many cases, can be integrated into a tiered model system to address students with developing problems . The findings from Project Follow Through, conducted in a variety of selected communities throughout the United States, suggested that Direct Instruction is the most effective model for teaching academic skills and for affective outcomes (e.g., self - esteem) of children . Recent large - scale studies (1997--2003), such as the Baltimore Curriculum Project, show that it is possible to help schools that are in the lowest twenty percent with respect to academic achievement steadily improve until they are performing well above average . In some cases, school achievement improved from the 16th percentile to above the 90th percentile . </P> <P> One three - year study of methods of teaching reading showed that highly scripted, teacher - directed methods of teaching reading were not as effective as traditional methods that allowed a more flexible approach . Urban teachers in particular expressed great concern over the DI's lack of sensitivity to issues of poverty, culture, and race . </P> <P> The former president of the National Science Teachers Association (NSTA), Anne Tweed, questioned whether direct instruction was the most effective science teaching strategy . In the December 15, 2004 NSTA Reports she concluded that "direct instruction alone cannot replace the in - depth experience with science concepts that inquiry - based strategies provide ." </P>

Studies of the direct instruction program have shown that it is