A polemic:

Yet a solution for the reading gap was discovered four decades ago. Starting in the late 1960s, Siegfried Engelmann led a government-sponsored investigation, Project Follow Through, that compared nine teaching methods and tracked their results in more than 75,000 children from kindergarten through third grade. It found that the Direct Instruction (DI) method of teaching reading was vastly more effective than any of the others for (drum roll, please) poor kids, including black ones. DI isn’t exactly complicated: Students are taught to sound out words rather than told to get the hang of recognizing words whole, and they are taught according to scripted drills that emphasize repetition and frequent student participation.

In a half-day preschool in Champaign-Urbana they founded, Engelmann and associates found that DI teaches four-year-olds to understand sounds, syllables, and rhyming. Its students went on to kindergarten reading at a second-grade level, with their mean IQ having jumped 25 points. In the 70s and 80s, similar results came from nine other sites nationwide, and since then, the evidence of DI’s effectiveness has been overwhelming, raising students’ reading scores in schools in Baltimore, Houston, Milwaukee, and other districts. A search for an occasion where DI was instituted and failed to improve students’ reading performance would be distinctly frustrating.