my villager found the drum and I had him tear it open. inside were some medical texts that made him an excellent healer.

what happens if you keep the drum intact? are there any community benefits to that? anyone know?

Yes!

aaaaahhhhh that's something I need to try

Aahhh the many choices and paths of the sim game

So what does it take to find the drum? Time? Or do you have to go around exploring?

It's an island event, and may or may not appear in any given game.

I makes it rain. So if you have no food or berries on the berry bush,the rain will make berries

That's one of the possibilities, but not the only one.

I've got another spoiler. I had a moth cocoon appear in my first game and I helped the moth to emerge - bad move .

I got that one too,AND I helped it. My brother got it, and he let it go. He got a master healer. NO FAIR!!!