Girlfriend is a primary school teacher and loves it – she's really good at it. A colleague of hers was a lawyer and jacked it in to teach – he's also glad he did.
On balance, it's no better or worse than most other jobs. You'll never be rich, but you'll always be comfortable. The work can be stressful if you're in a rubbish school with poor colleagues, or great in a better behaved school with more skilled colleagues. The holidays – you'll have a bit of work to do but can usually bat through this in the first 20% of the holiday – you'll never be more than a few weeks away from a break.
On occasion you might have to work a bit later than usual, but in my experience, nowhere near as hard or late as you might do in another challenging industry (I work in advertising)
If I wasn't so uncomfortable with kids, I'd sign up in a flash.