I found a way to make your sim meet every teen in the game including your own CAS Sims

If you have Get Together, just create a club and make the age requirement teen - it will let you choose every teen and add 5 to your club.

Once added and created, kick them out and add another 5 - repeat the process and in less than a couple of real life minutes you will know every teen sim in the game and never even need to leave your lot.