Thanks for the responses! I've gotten several of my questions answered via PM (thanks!). Here's the deal: I am completely ignorant when it comes to horn instruments or mouth pieces or spit guards, etc. My questions (so far):
1. How difficult is it to play a baritone for a 10-year old? It appears to be a lot of work to me.
It's a big horn for a little guy. But as it is with any wind instrument, it's going to take time and commitment before anything resembling music comes out of it.
He should concentrate on getting a good sound out of it at first and holding the notes as long as he can. He should practice what is known as diaphramatic breathing where air is taken into the lungs from the bottom and supported by the diaphram. Have his teacher at school explain it to him.
They're not cheap. A basic student model can probably run about $1000 and a top of the line pro model can fetch somewhere in the neighborhood of 7 or 8 thousand. There's an online retailer called The Woodwind and Brasswind. They're pretty good. Also maybe eBay for a used horn.
I wouldn't push him. If he's into it, he'll want to play on his own.
Someone recommended personal lessons. I think that's an awesome idea.
Always a good idea. The teacher at school can only devote so much time to each student and if he's not a brass specialist, he might not know the finer points of brass playing.
TIA