My daughter plays in the FJ4 (10 and under) division and uses putters, mids and drivers. Her main drivers are a 147g Lat64 Diamond and a 150g D XL. She also used a DX Shark at 150g but was flipping the crap out of it before she lost it in a river. Her distance has been mesured at 231' in a long arm competition.
When she first started she was using a 150g Aviar P/A, a 150g DX Shark, and a 150g XL. The XL was a little much when she started, but it gave us an opportunity to work on form and arm speed when dealing with drivers. We also went through body position and runup in regards to the basket and how the disc acts in flight.
What we've learned is that drivers are ok, just don't teach OAT to get the disc out flat, just build an understanding that this disc will have to be aimed left or right of the target. Mids are better in a little bit of a heavier weight as you get closer to the basket. Skeet or Shark at 150g from a 100' out, and she uses a 162g Ryho any closer than that. Aviars at 150g are great for little arms unless the wind comes up. She use a 165g for those cases, the deal being she needs to make that decision and learn that aspect of the game too.
She is of average build, intelligence, and athletic skill, but she is consitent, consistent, consistent.
There is too much info to post here, if you want to PM me thats cool.