Summer school for HS kid who had a bad year academically?

My sophomore son had an extremely tough year. His high school doesn’t offer summer school. Can anyone in CT tell me what can he do for grade recovery, or what? His overworked/new/young guidance counselor is “trying to find out” what - if anything can be done. Also wondering if he can take a course elsewhere, not offered by his high school, and receive high school credit for it? Where to start? TIA

There are many private high schools, both day & boarding, in Connecticut that offer summer courses. If you live near any private high school, call that school and ask about summer program offerings. For example, The Taft School is one option to consider.