Scooters and children

What is the law exactly here?
Are they allowed as long as they wear helmet?
Can they crap along above certain age?

My husbands standard answer whenever I shake my head in disbelief after seeing a packfull scooter with children is:
Everybody do it!

-My answer is: Yes, but is it LEGAL!?

…so…can someone give my some info?

Thanks,
tine (non-scooter-driver only baby-stroller-driver)

As far as I’m aware… it’s not legal… but the cops don’t usually do anything…