[WORLD_ENDS_SOON]

I'm guessing information isn't put in the email because of federal privacy laws around education (FERPA). Email isn't considered a secure communication protocol since it isn't encrypted in transit, so schools can't email grades or other information related to education records. I'm guessing sending all messages through a secure web portal is just an easy way to avoid FERPA liability from the schools perspective.

[aaplok]

I'm not in the US but you make a good point. They probably need to confirm parents' identities. An easy and well advertised low tech solution would be good for low tech parents though.