1. If you are not in possession of large (or at least relatively large) breasts, you will never be as popular or well-liked as the girls who are more generously endowed. You also think that this will somehow dissipate as time goes on, but (at least in bars) it continues to be shockingly true.
2. No matter how good you are feeling about yourself, one snide or negative comment from someone you really admire or have a crush on will ruin everything about you. You could go from winning the Nobel Peace Prize to crying incoherently into your Snuggie with one word from a popular girl.
3. You can maintain long, complex friendships with people you really don’t even like all that much simply because you are in the same social circles and in constant proximity with one another. No matter how much the two of you may actually have a strong mutual dislike for one another, as long as you don’t verbalize it, your friendship can last for years on end.
4. If you have sex with anyone — no matter what the circumstances — you are going to be a slut with a terrible reputation. If you don’t have sex with anyone — no matter what the reason — you are going to be a prude with an icy reputation. No matter what your sexual activity level, there will be a comment to make, and if you don’t reveal it to anyone, people will make up their own story for you.
5. You should neither be too skinny nor too big, lest you be a “stick figure that needs to eat a cheeseburger” or a “fatass who needs to go to the gym.”
6. If you like someone, chances are that everyone else is going to know about it besides the person whom you like — and the person you like is most likely going to find out through the rumor mill, rather than you actually working up the courage to tell them.
7. Having a driver’s license literally changes everything.
8. Not being invited to a party is the second-worst thing that can possibly happen to you, after being invited to said party out of pity or obligation.
9. People will tell you, to be inspirational and positive, that you should “go against the grain” and “be yourself” when it comes to things like fashion or personal expression. What they don’t tell you is that, if you actually do this, you will suffer enormous amounts of ridicule from your peers and possibly even your authority figures.
10. The internet has the capacity to be both your best friend and worst enemy. While there is nothing better than having an at least semi-anonymous way to express yourself, everything you put on there actually lasts forever.
11. Breaking up is something that will inevitably involve everyone around you, because no one can witness a relationship ending near them without invasively asking at every turn “What happened?!?” “Who dumped whom?!?” “Are you still friends?!?!??!”
12. There is never a wrong time to kiss your significant other when no one is looking. Even the locker banks between classes is a suitable locale, as long as the administrators on duty have their backs turned.
13. Never tell someone a secret that you intend to remain a secret. No matter how close you consider this person (with the possibly exception of your one true best friend), some way or another, the secret is going to find its way to everyone you’ve ever met.
14. One zit has the capacity to ruin your entire week.
15. Out of the many people you will implore to “KIT” when signing yearbooks come graduation time, you will probably only remain close with a very select few. And, as you will come to realize, this is probably for the best. You don’t really need to “KIT” with that random girl you once hung out with during the chorus field trip, you only think you do. 
