If you’ve been playing tennis outside of school at say, a club, is it still okay for you to try out for a tennis team in college, or do they really only want the kids who’ve played at high schools? Mine doesn’t have a team (STEM high school) and I played for my sending school on varsity for the summer and part of the fall until a lot of scheduling issues forced me to stop.
The tennis team likely wants students who can play tennis well, regardless of where they trained. You should try out if you want to.
You should definitely try out! It’s also possible you have a club team that’s not quite as competitive, if you don’t think you’re on the level of NCAA sports.
Thanks guys! 
For the school’s official team? probably not at a D1 school. For a school’s club team? sure, I’ve seen lots of kids join that weren’t part of their high school team. But also these guys were USTA ranked super champs who thought their high school team was not challenging enough…
Oh wow haha. I’ve been told I’m pretty good (my coach is a regional champion apparently) but honestly, I’d do it for the workout and for a break from studying so even if I don’t make the official team, I’d be completely okay with a club team.