I don't think he'll be the odd one out. No odder than being the kid with glasses or the kid who runs fast.
If he lives in the Eastern suburbs in Sydney or any area with a high Jewish or Muslim population he might be the odd one out if he's not circumcised.

How much time do boys at school spend looking at each others' penises anyway?

There are times that I worry about my boy being the odd one out or not fitting in but never because of his penis.

Both my boys were circumcised before 8 weeks. I had no issues finding Drs to do it. In fact I had a choice of Drs, settings, anesthesia and methods. They didn't appear particularly traumatised to me but what would I know, I'm just their Mum