I rode at Baskin Farm for several years while living in St. Louis, and it has the best trainers I've ever had (and I've had a lot of trainers). They have around 15-20 lesson horses with a huge lesson program, which is really great! They also have great boarding; they take great care of their horses. The trainers and staff are really awesome!
Pros: competitive for people who are competitive and fun for people who just want to learn how to ride