It's so cool that you're being so supportive of your kids. Especially if they become "really good" (which I'm sure they will!) you will be doing a lot of work yourself, fundraising, hauling them to clinics, lessons, masterclasses, honor bands etc. But seriously they'll appreciate it. I played a total of 4 instruments during my 7 years of band (flute, tenor sax, piano, and french horn) and I feel like I'm a better person for it. My sister is a drummer, so you have my sympathies! Maybe you'll luck out and he'll like the xylophone or marimba so he can only practice at school.
