This story takes place in an alternate universe (they are humans, not ponies).
Twilight Sparkle is given a Scholarship to attend Headmistress Celestia and Vice Headmistress Luna's Princess Preparatory, a school for young Princesses in the making. This is because her brother, Shining Armor, is attending the school's "brother school"; Prince and Knight Academy. Which is led by Headmaster Thorax and Vice Headmaster Pharynx. Shining attends because he is courting Princess Cadence, who is like Twilight's sister. Her brother, Spike, is with Shining at Prince Academy. Twilight Sparkle meets six other girls, who are born Princesses. They help her to succeed in the Royal School. But there are many obstacles they must face.
Meanwhile, at Prince and Knight Academy, Shining Armor and Spike have made friends with five certain boys. When they are asked to have a joint class with the ladies of Princess Prepratory, they fall in love with certain girls. Together the boys and girls strive to complete their years and graduate, working together to solve problems (and fall in love while they're at it)
(boys are in the story a medium amount but there's not enough number of tags to include them)
Important Ships in story:
Soarindash
Shining x Cadence
AppleSpike
Rarity x Fashion Plate
CheesePie
Twilight x Star Tracker
Fluttercord
Starburst (Starlight x Sunburst)
Sunset Shimmer x Flash Sentry
Spitfire x Fleetfoot