"What I wish someone had told me about high school": ever wish you had a cool older sister who would tell you everything you needed to know to make high school the best time you've ever had? We got 17 seniors to spill on what even your big sister doesn't know

Girls' Life, August-Sept, 2004 by Allison Davis

#12 Avoid freshman burnout.

Even if you ignore our previous advice about keeping on top of homework, remember this: Don't pull all-nighters for a week to get the work done. There will be times when it seems like every class has a huge project due. If you're feeling overwhelmed, talk to your teachers. Most will be cool and give you an extension, as long as you have a valid excuse. No, "I was watching an O.C. marathon on Fox" doesn't count.

#13 Mistakes are OK.

Everyone trips up every now and then, even teachers, coaches and parents. It may not feel like it, but nobody expects you to be perfect all the time. The important thing is to learn from mistakes, and just let go of failure. The truth is, making mistakes can actually build character. Getting busted for being a gossip, for example, can teach you that bad-mouthing people usually backfires. Keep your lips zipped from that point on, and you'll be known as the girl who only has good things to say about others.

#14 Take care of yourself.

It might seem impossible to forget to do basic things like eat and sleep but, trust us, it is incredibly easy. You have to stay healthy, so eat right and get plenty of sleep. Susanna recounts a night she chose studying over sleep: "I tried to study from 12 a.m to 2 a.m. Needless to say, I bombed the test. I probably would've done better if I had gotten a full night's sleep and woken up early to study." At times, you might have to sacrifice an A for some Z's.

#15 College? Forget about it for now!

Freshman year is not the time to plan your college career. You might swear, "Harvard is the only place I'd ever want to go." Kudos to you for being so clear about your goals. But chances are your goals will change. When I was a freshman, I didn't even know mg college existed. Leave the college anxiety to the upperclassmen--you'll have plenty of time to deal with that later.

#16 Life isn't defined by milestones.

You'll probably experience a lot of firsts in high school--first boyfriend, first D, first prom. But high school is more than a series of firsts and lasts--it's about all that great stuff that happens in between.

As Melissa says, "I'll always remember random times during play rehearsals when we'd all hang out and talk while we made props. Or Friday nights spent driving around, singing along to bad '80s songs with my friends." As cheesy as it sounds, the next four years are going to fly by. So make every little moment--the good, the bad and the ugly--count just as much as the big ones. Got it?