I was thinking about that when I was dropping my 6 year old off at some hobbies earlier - it's pretty much expected to have learned how to ride a bicycle before starting school, and it massively expands the area you can go to by yourself. When she went to school by bicycle she can easily make a detour via a shop to spend some pocket money before coming home, while by foot that'd be rather time consuming.
Quite a lot of friends from outside of Europe either can't ride a bicycle, or were learning it as adult after moving here, though.
edit: the high number of replies mentioning "swimming" made me realize that I had that filed as a basic skill pretty much everybody has - probably due to swimming lessons being a mandatory part of school education here.
That leads to a follow up question to people from different areas: Is swimming a regular part of school sports?
I grew up in Germany with pretty much no lakes, and we had blocks of sports classes in the swimming pool from first grade - didn't make me a great swimmer, but I can go swim a bit in a lake without having to worry.
Now we're in Finland (lots of lakes here), and also swimming classes take place from first grade.
American here. The nearest swimming pool to my hometown was in Canada. So no.
Edit: I don't think this is normal
How big distances / population are we talking here?
I was growing up in a small village, so in elementary school we went by bus to a nearby village with 7000 inhabitants and a swimming pool.
Now we're living in a town with a population of 46000 with its own swimming pool.
Yeah, a small village. It would have been a half-hour bus ride to the town of ~5000, but they couldn't compel all students to get a passport, and the nearest pool in the US would have been about an hour and a half away, so it was never part of the curriculum. Some kids had their parents drive them to Canada after school for private (expensive?) swimming lessons, but it wasn't standard.