Artist's description from DA:Twilight- Absolute stereotypical nerd. Braces, thick glasses, scrawny and socially inept. She was beyond studious and was routinely sleep deprived from reading all night long.
Fluttershy- Now so, so shy and adjusted to being picked upon. She dyed her hair for a few years in an attempt to fit in, but with little to no success. She was friends with Rainbow, but that didn't lessen the abuse.
Applejack- She went through a bit of a grunge phase, especially due to the death of her parents a few years prior to. She didn't do very well in school, with the exception of gym class, and preferred
RD- Total daredevil and stunt buff. She's battered and banged up from trying out new flight maneuvers and tricks. Despite trying to seem like a total badass she never did all
Rares- Queen Bee and popular diva Rarity was known for being the prettiest mare at her private school, and not just because she really caked on the make up. Soccer star and Class President, every pony wanted to be her or be friends with her.
Pinkie Pie- finally out of her shell, she exploded with color and energy. She didn't have as many friends as you might think, becasue all her classmates thought she was too weird and loud. She mostly spent her time with her sisters, the other rejects, or the one friend she had from the cheerleading squad.