M.S.
my husband has coached for years, before ours were even born...his most appreciated gifts have been gift certificates or homemade treats. while photos in frames are nice, there's only so much room in a house or office to display them. gift certificates to sports stores (because yes, he has on occasion, put forward his own money for equipment) or a restaurant are probably the best. If you want to limit the $$, a heartfelt thank you note is all that's needed.