How many square feet would a bakery have to be minimally?

A cake decorating school fit to fit (no pun intended) 10 students (with ovens and everything)?

I'd say your question is wide open with a lot of "depends".

What your primary products will be will dictate your equipment needs. Lots of doughnuts? Deep fryers! Decorated cookies? Lots of table space and stacked ovens. By order only or on demand (on spec)? That will dictate your cold storage demands. Just in time delivery daily or a weekly delivery? That will determine your dry storage. And your cold storage, come to think of it. Hand washing the dishes/pans or commercial dishwasher? Can one 3-compartment sink handle the volume of dishwashing in your full scale bakery or will you need 2 of them?

Lots of factors in this one!

A small cake shop would be comfy with 800sf. I say the more the better.
I have 1760sf and probably realistically only need 1200.
mpc

Mine is about 1100sq ft and it's just the perfect size for what I want to do which is appointment only but since I am doing walk-in also I need about 200 more sq ft.

My total space is 1100-1200 sq ft and I also do catering. This space includes a front office/sampling area to meet with clients.

i got about 1100 sq ft.

truthfully alot of the space is wasted...i could get by with 800....