Why is Duolingo blocked on my school's chromebooks?

So, my high school has chromebooks for students to use. The other day, I finished my work early, so I decided to go onto Duolingo. But, it says the website was blocked. Is there any reason why it would be blocked? A bunch of other websites are unblocked; Discord, Reddit (which is actually how I’m writing this right now) and whatnot. So why would an educational website be blocked, of all things? Just curious.

because it promotes eating mustard with ice cream

It doesn’t meet the legal requirements some places for student privacy.
The non-educational sites don’t have to meet that requirement.
Don’t ask me why.

Teachers at school don’t know, I don’t know how to contact school board, and I doubt they’d respond anyways.

And mayonnaise on cereal!

Oh, that’s strange. Thank you!