It is my understanding that the rule is, half the height between the elbow and ground under a year of age. Also goes lower the younger the pup and the large/heavier the breed. Which is why jump bumps are used for pups instead of jumps of any height. Airn, nothing wrong with teaching solid foundations to pups, actually it is recommended. But there is a big difference in flatwork foundations and running sequences and piece work. Pups can learn impulse control, wicked recalls, shadow handling (heeling on both sides, at all speeds, walking, stopping, running etc) learning to run past obstacles and tunnel entrances without doing them is far more important at this age/stage than doing them. Plank work and developing a end contact criteria is also excellent. We also don't teach weaves to young puppies. Proofing recalls, stays and working during distractions, something as simple as tugging around other dogs or while other dogs are working. The hardest thing to do, is keeping your pup with you and focused on you in a distracting enviroment. We also want dogs/pups to look forward and not at us when doing agility, so a lot of work in put into teaching them to focus forward, it is called handler v.s task/obstacle focus. There is so much to train which can benefit a pup, regardless of whether you do agility for non competitive or with goals to compete.