duct tape and cinder blocks...
I take pics of my spazzy children all the time. I highly recommend the auto-bubble thing. Makes for some great shots. I also get a lot of good pictures of the kids just playing... with their bikes, with each other, etc. That's what kids are all about, after all... just watch that when you do this, you don't have anything ugly in the shot... that can be a bit challenging. Shots of kids playing with water also tends to be a big winner... give most kids a hose and some places where water makes puddles and they'll be happy for hours.
Try to find out ahead what the kid likes and doesn't like, ask the parents what his favorite places are, etc. Try to pick a location that will work for him and for your photography. Sometimes new places that aren't even super fun for kids can be fun for a while, and at least long enough to get a shot.
Generally I shoot a lot and toss quite a few. They just move around too damned much.
Depending on the kid, sometimes you can get them to just sit for a moment or two, and it's great if you can get them to sit with mom/dad/the dog/other siblings.
Remember to try not to take all your shots from a standing position looking down. Try to get a lot from down at their level, and possibly down lower on occasion- just watch your background sky when you do this... try to make sure the light is on the kid and to your back.
If taking pictures outdoors (which I'm obviously assuming you will be), bring a polarizing filter. If you don't have one, get one before hand. You won't regret it.
If taking pictures indoors, make sure to have an external flash with indirect flash capabilities and ideally a diffuser as well.
Remember to take advantage of the rule of thirds, and also try to focus on their eyes.
Remember your DOF... kids are going to be in various random places and distracting crap in the background will instantly ruin any shot.
Just some ideas... hope my stream of consiousness (sp) is helpful. Good luck! I hope you'll post some!
