Getting an invitation to join/get an award et al doesn’t always mean anything. I would not bother with most- especially if you need to pay for it. In middle school son could have gotten something or other- meaningless. Being listed in those books of top whatever/who’s who is worthless ( I look at those as a list of foolish parents who bought the listing- the smartest don’t bother). I even got offers for physician ones after being retired!
The National Merit program is worth following up on if offered. Academic summer programs that interest your child are- especially through Talent Search programs (different regions covered by different programs through respected colleges and some states). Many of the others are pure junk and meaningless on application forms. They, like vacation mission trips, just show you and your child had the money to participate. Check with gifted and talented websites for discovering opportunities that are legit. Summer camps offered by colleges are legit. There are some good language camps.