Is there a recommended number of tutoring hours per week for the Orton-Gillingham Approach to be effective?

The most common instructional pattern to be employed by Orton-Gillingham practitioners is the 1:1 model. This includes at least two independent sessions per week, each with a duration of 40-60 minutes on non-consecutive days. Typical patterning of the two sessions calls for an intervening day between sessions. Variations in this pattern may range from a single session per week (of one or more hours) to students who attend schools expressly designed for students with dyslexia. In the latter cases, Orton-Gillingham instruction is daily. The most important thing is that every effort should be made to structure Orton-Gillingham instruction to fit the learning needs of the particular student.