Unfortunately our kids weren't allowed to cycle to school unaccompanied by an adult until they reached year 4 and had passed their cycling proficiency test (mid-way through that school year).

I've been cycling with my daughter to kindergarten for at least a year, she's fine with the cycling bit, it's the looking-out-for-other-vehicles bit that's not quite there yet :/ This obviously depends a lot on local road layouts, and unfortunately we have a junction more or less right outside the school and kindergarten that way too many car drivers come through at speed...