Alastair McKnight has just sabotaged his own summer plans by breaking his collarbone while careening along on a ""dog-powered skateboard train."" Chafing at his confinement, he's delighted to find a tiny four-pound dragon, eating Mom's petunias. Alastair hides little ""Spike"" in his room, discovers that he's vegetarian, researches dragons in library books (could this benign specimen be Chinese?), and uses a mop to disguise Spike as a dog in order to walk him--his droppings are peculiarly noxious. Eventually, the secret comes out, but researcher Uncle George--with whom Alastair has been in correspondence--turns up just in time to guarantee that Alastair gets to keep his unusual pet. A simple story, but Seabrooke (the widely praised Judy Scuppernong, 1990, etc.) tells it with humor and imagination, providing plenty of amusing details--especially the antics of Spike, a kittenish creature who bursts into flame only occasionally and, luckily, doesn't grow at all. Appealing fantasy in a briskly drawn realistic setting.