I'm fortunate in that my kids all started in Catholic Grammar Schools, and then of their own volition chose to continue on to Catholic Prep High Schools (which of course made me happy). I like the Catholic Preps for a lot of reasons, but one of them is they very strongly push and celebrate academics.
In my high school back in the day, the debate & forensics team was the premier team in the entire school, and pushed strongly by the academicians and administrators as a source of pride! It held the top status, was taken the most serious, and reflected the most pride along with being known as difficult for a member to be picked to represent the school in competition (even though all could join and participate in the research & prep-work).
We also had very good football & wrestling teams, but the Catholic Brothers and Priests really pushed academics and instilled a culture desiring academic excellence. For my extracurricular activities I played sports as an offset to my academics, but we were constantly reminded by the coaches that we were "student-athletes", and that the 'student' part of that compound word precedes the 'athlete' part, so being a good 'student' always comes firstly.
Back then to be sports eligible you had to be running a cumulative 'B' average with no more than two 'C's and no grade lower than 'C', and your coursework for each subject each week had to be at that same standard. If your weekly coursework slipped below those standards, the instructor for that course sent a form that circulated to all your coaches. You then were expected to bring your grade up within a week. If you didn't, you and your coaches were given notice of another week to correct the deficiency. After two weeks of deficiency you were ineligible for sports.
The thing with this is: The coaches and the teammates put huge pressure on kids with poor academics. Especially on the big teams like football. No one wants to expend a ton of teamwork & effort, only to find-out a key player is ineligible due to poor academics! The slacking guys were seriously ostracized!
This is the type of environment I wanted for my son, and I was happy as hell he not just chose, but embraced the same. Obviously his academic success is his own, but I feel very strongly that his peer environment contributed strongly to his academic successes.