As Brian said Give a caresheet to the mom. And also possibly SHOW him proper care for it. Many people learn from example. For garters, nightcrawlers are not really a bad thing, the spiders is pretty much a joke. Goldfish are good for them too. Mice are on the diet too. If the intent is to just keep the snake to see how long it will live without proper care. If thats the case I would tell him the snake likes to be outside sometimes, and have it escape.
Don't forget ReptileFest April 3rd-4th