The chasing instinct helped our canine ancestors catch prey, and many of us dogs still like to chase anything that moves.
Nevertheless, you’re right to be concerned, and you are wise to keep your dog in a fenced yard or on leash. Also, neutering your dog was a good decision, because neutering decreases the risk of dog bites.
To teach your dog to remain calm around kids on wheels, you’ll need to begin a training program.
Start by teaching your dog to look at you on cue. Stand before your dog, touch the corner of your eye and say, "Look!"
When your dog looks at you, even if only for a moment, praise him and offer him a treat.
Next, teach him the cue to “leave it.” Drop some food or a favorite toy on the floor, and walk by it with your dog on leash.
Tell him to “leave it,” and reward him as he walks by without going after it.
Finally, teach him to “stay” with the same praise-and-treat technique. When he can sit (or lie down) and stay for several minutes in the house, move outside.
Work on these three concepts –- look, leave it and stay –- around minor distractions, and then around children on bikes and skateboards.
Your goal is to have your dog look to you for guidance when he sees something he’d like to chase.
If you’re walking along the sidewalk and a child rolls by on a skateboard, he should “leave it” when you tell him to.
If you’re standing in the yard and a child rides by on a bike, your dog should “stay” when told.
For additional assistance, join a dog obedience class.
Avoid punishing your dog for chasing. Punishment can cause aggression if the dog associates the moving child with pain or chastisement.
So train your dog with praise and treats, and soon he’ll sit calmly as the children roll by.