Studies show that students who receive high-impact tutoring that is directly related to their in-class curriculum can translated to an addition 3-15 months of additional learning. At Educational Harbor, we have found that a 30 minute tutoring session once per week translates to an average of 4-6 months of additional learning. Our tutoring does have characteristics of "high impact" as defined by research, which includes cohesion between the tutoring session and the student's curriculum, targeting specific learning needs and deficiencies, and use of data.

High-Impact Tutoring: State of the Research and Priorities for Future Learning (edworkingpapers.com)