Hilarious but valuable lessons 'Mean Girls' taught us

MANILA, Philippines – Every 'Mean Girl' fan knows that you can’t wear a tank top two days in a row and you can only wear your hair in a ponytail once a week.

But those are not the only rules that can be picked up from the movie. Apparently, there is more to the Tina Faye-penned teen comedy movie than being just a movie showing a trio of attractive bullies preying over the whole campus.

In celebration of  the 10th anniversary of “Mean Girls,” here are some of the valuable lessons we have learned from the movie which raked nearly $130 million sales worldwide and have been dubbed as the Millennial Generation's "Clueless."

There is always that someone who seems to know everything about almost anything.

That little one, that's Gretchen Weiners. Gretchen Weiners knows everybody's business. She knows everything about everyone.

Peer pressure really exists among teenagers.

I saw Cady Heron wearing army pants and flip flops, so I bought army pants and flip flops.

You don’t always get what you want.

Gretchen, stop trying to make 'Fetch' happen. It's not going to happen.

Accept others for who they are and stop comparing yourself with other people.

Calling somebody else fat won't make you any skinnier. Calling someone stupid doesn't make you any smarter. And ruining Regina George's life definitely didn't make me any happier. All you can do in life is try to solve the problem in front of you.

Respect your BFF.

Ex-boyfriends are off-limits to friends. That’s just, like, the rules of feminism.

Never pretend to be dumb just to get someone’s attention ... even if he is really cute.

I pretended to be bad at math so you would help me.

Some questions are meant to be withheld. Especially if it is about people's color.

So if you are from Africa, why are you white?

Some girls are self-consumed and too insensitive to admit it to themselves.

I'm sorry if people are jealous of me. But I can't help it that I'm popular.