Nope, any age (and size) is fine as long as the dog is physically fit enough to do it.

Look around the internet for agility trainers/clubs. An obedience trainer may be able to recommend an agility place as well. You can also look for agility clubs that might offer lessons.

I'm hoping to get the boys into agility soon. It's supposed to help with building up confidence. Kaedyn is fearful of many things and doesn't know how to trust so I'm hoping agility will bring him out of his shell. Kai is also very shy and fearful.

We did jumps in obedience last week. For the past 5 weeks, he has been extremely fearful during classes because he's generally afraid of people and especially men. After 5 minutes on the jumps, he started having a good time and actually wanted to play! It really brought him out of his shell.