Hey, I really want to know this: why does Minnie speak so weird?

since the siblings dont go to school they have private tutuor. she was tuaght by Helga patacky (adult). from "hey arnold" if you wacth Hey Arnold you will see helga is a very poetic speaker when she has her private momments confessing her love for arnold. minnie was a quick learner and developed a shakespere like speaking pattern

i think it's because she was taught old english by her teacher

because she was taught by a teacher who was very old fashioned and made her into a lil princess basically. If you read "memories" in the comic after junior recieves her eye u see her learning things as archery,balance,fencing and receiviing a gift from grim.

Hey, don't diss the Minnie, man.

I think her private tutor teaches her the polite language.

Minnie and Jr. both were tought by Ms. Pataki their private tutor (Pataki as in Helga Pataki. 90s kids will know). anyway minnie is said to have spent all her spare time with miss Pataki so she ended up learning how to speak the 'Proper' way.