no cami please. If you feel too exposed, ad a neckless (v-shaped in a dark colour that almost hits the top of the dress) put your hair down to cover some shoulder, and pair it with flat dressy sandles. Definitely not to school.
Wow. I can't imagine you wouldn't be sent home in this. Too skimpy on top, and too short for school. The dress is too full on the bottom for such a short length. Full skirts need to be long, or they just look poofy.
The shrug is a little too casual for the dress (which is fantastic!). I'd try a dark coloured shrug (maybe a plum/purple) to really make the colours in the dress pop.
This is really cute - I like the sweater with it. It seems a bit formal for school but it sounds like school is more formal than when I was in it! Cute sandals would be my choice but you could throw on a heel to make it more dressy.