I'm not that familiar with boys showcases but I'd imagine Surf Cup in Del Mar (end of July) is a big one for both girls and boys for college recruiting.
Surf Cup for sure as stated above, but for the guys if you don't end up in Best of the Best there will not be that many coaches showing up to the games. But some. Surf College Cup and Man City, same thing, although I thought the bracketing for Man City seemed better. I think it is sort of a different process on the women's side but for the guys a more productive approach may be to send an interest email and a link with highlight footage, your twitter feed, etc. to colleges of interest. If they have an interest in you or at least interested in recruiting for your position, they may be willing to come give you a look at whatever venue works. The ID camps are kind of a racket but, if you apply to the school first and get in, then go to the camp as a senior they may be more willing to give you a real look. "Admission by exception" is really not that much of a thing anymore. And at the camps right now, the coaches are saying "look, we know the alphabet soup on the guy's side doesn't really mean much anymore, and we just can't scout all of SoCal. We sent a scout to MLS Next championship, ECNL whatever national tournament and it was largely a waste of time and money". Heard that at least two camps. Could be part of the racket-who knows. If playing college ball is a must have and the academic part of the fit is really flex, going into senior year set up an account on Field Level. It is one of those app things. Most of those apps nobody pays any attention to but for some reason Field Level draws interest from many coaches at smaller state schools and private schools across the midwest. If you are a decent player they will contact you. But bottom line, at least from what I've seen over the last two years, for the guys if you think just getting into the right tourney is going to get you recruited that may be a bit too optimistic. Even for the better MLS Next or ECNL guys teams, the ONLY time I saw LOTs of college scouts at a game was for LAFC U19s who were playing in USL and for some reason entered the Surf College Cup. Which I thought was kind of funny given that most of those kids were hoping to go pro.