I agree with previous posters who mentioned crafts. My 10-year-old son doesn’t like sports but is always looking for new projects to try. During the summer he plants flowers & vegetables. His latest hobby is origami.
A.C. Moore & other craft stores (if you have internet access you can find store coupons online) are a good source for craft & projects kits. Your sons may also enjoy caring for small pets like freshwater fish or an ant farm. Kids that age sometimes enjoy easy science experiments such as making rock candy (you can add food coloring to make it look fancier).