Dear Rainbow Dash:
Twilight offered to teach you all about the Wonderbolts? But didn't she banish all pegasi from her library? Ah well, she probably changed her mind when she realized that she couldn't invite her favorite pegasus over anymore.
Now, about the studying. I must admit, I'm quite proud of Twilight. She clearly takes after me when she's educating other ponies. That said, I don't remember ever being that obsessed with flash cards. I can't help but feel that there's a reason for that.
Still, maybe my methods aren't the best, so perhaps Fluttershy could helpful. After all, she helped Discord learn the importance of the magic of friendship, so there's no possible way she could fail now! I mean, she even got your turtle to be part of her study methods, so you probably learned a lot, didn't you?
...No? Oh well, there's always a much more fun way to teach kids: Rap! I mean, not only does it include catchy beats and funky clothes, it's also just one letter away from my favorite word of all time! And if there's one pony who knows exactly how to make those raps stick, it's Pinkie Pie!
If that fails, I know Rarity will try to translate her knowledge of clothes into knowledge of Wonderbolts. At that point, though, you're probably scraping the bottom of the barrel. As for Applejack... ah, you're probably doomed.
Of course, if by some miracle Twilight was able to find a way for you to retain all that Wonderbolt trivia, you'd probably forget it after a week. I mean, does anypony remember everything they learned in school? Hell, I doubt anypony needs to know anything they ever cover in their exams, so why do we bother making sure they don't cheat?
In any case, any time you need to study, you're always welcome to come to my dungeon study room. I may not have flash cards, but I do have a "Flash" there who could probably help you study!
Your future teacher, Princess Celestia.
P.S.: Don't worry about bringing whipped cream or rulers. I have plenty here!