Welcome to SA!!! You're gonna love it here!!!
Please consider River City Community Church (www.reallife.org). That is our church. We have a wonderful Youth Group...If I had to guess, I'd say about 60 students at any given time...Of course, that's MY guess.
Both of my children are heavily involved in the Youth (my step daughter [15, Sophomore] is too when she visits us and has kept a lot of these friends online when she is back home). My eldest (17, Junior) leads Worship and is a Core member. My little one (11, 6th grade) is working her way into Worship.
They have weekly meetings (Wednesdays), two services geared for the Youth on Sundays, monthly service projects and other activities throughout the year (ie - Youth Christmas, Bond Fire, 5th Quarter, lock-ins, etc.)...and they are planning a major Mission Trip this summer.
I spoke to my eldest this morning after reading your post and she said she'd be more than happy to meet your son before Youth on Wednesdays or a Sunday to introduce him to some of the group and the leaders.
We are located at Redland Road and Jones Maltsberger (you can take 1604 West, exit Redland Road, turn left and you will run into RCCC on the right, at the corner of Redland and Jonesy).
We are not LARGE (like CBC or Cornerstone)...But it works for us. I know it's important for you son to be plugged in...Our kids walked in 4 years ago and were welcomed like they had been there for years. THAT was a comfort to us, to know they were plugged in, loved and cared about.
Contact me at ____@____.com if I can answer anymore questions. Hope to see you ALL soon!!!