I think having four of my own children has flipped a switch of some sort because I spent most of my life pre-children wanting to teach more than anything else. The fulfilment from watching a child grasp a new concept, gain confidence in something they found challenging, getting to organise the classroom MY way (rofl.....) all seemed incredibly attractive. I loved the few years I taught full time too. However it would seem my "small child" energy supply is seriously depleted after nearly 12 years and reserved solely for my own small (and the not-so-small) children.
I've started volunteering at H's school - literally just started today, but the "buzz" I used to get on entering a Primary School just isn't there.... and something tells me it may have migrated to the coffee shop with the cappuccino, comfy chair and a newspaper. Maybe it requires sufficient sleep to generate enthusiasm but I don't think that's it to be honest. I think I've moved on - not sure where to just yet but watch this space!