Intervention instruction is frequent, regular, and of sufficient duration to make a difference.

All of the successful programs offer students special instruction on a daily basis for periods ranging from 20 to 45 minutes. Daily contact with students ensures that progress is steady and allows teachers to become very familiar with students and their strengths and needs. Frequent contact also allows teachers to reinforce and extend strategic behaviors that students are acquiring. An instructional period of at least 20 to 30 minutes allows time for instruction and practice along a number of dimensions that provide students with the strategies they need to become effective readers.

In terms of duration, the Reading Recovery Program limits student participation in the program to one hundred sessions, the philosophy being that if a child is not "discontinued" (the term for meeting the criteria required to function successfully in the middle range of student's regular classroom without special support), some other form of special support is needed.

The prevailing philosophy in most of the other early intervention programs appears to be that first grade is the point where special help should be offered to prevent reading failure; that many, if not most, students will, by the end of first grade, be able to make sufficient progress in reading to function in a regular classroom setting without special help; but that some students will continue to need support through second grade. Though some of the programs began as just first grade programs, most now continue through second grade for students who need longer periods of special help.