Possibly the ACHIEVE program
I do not know if they are active in the summer.
Program manager Shannon Kirk
skirk@somsd.k12.nj.us
This sounds pretty intense and expensive but in case you don't know of it:
Saturday July 18 - Garage Sale: 528 Prospect St. 9am-2pm Sale Date: Jul 18, 2026
More info

Does anyone know where a high school student could go to increase their reading speed and retention and also their writing skills?