In the U.S., several states and Washington D.C. have laws that require employers to provide time off for parents/guardians to attend school events. The laws vary by state, but here is a breakdown.
Apparently, there's a Facebook post going around about this, but I'm not on FB and only saw it in my daily headlines. Personally, I've never seen this in any “employee handbook” even though my state has had a law on the books since 1993. I thought other people might be in the dark too, so I wanted to share.