I truly do not know about summer courses.
We are going to Europe for six weeks and Ghost will have to do Boy Scout camp (otherwise it will be very difficult to get some of the obscure requirements out of the way for an Eagle).
I would love for him to do Math Path, but I don't think that he is very interested. Plus it is very expensive.
We were thinking about THINK, but if he goes, there is going to be almost no family time here at home over the summer.
My daughter is writing Explore for the first time this winter. It would be interesting to see if she qualifies for any summer programs and if she would be interested in going. So far she is also planning a Girl Scout camp with her troop.