Girl saying lol in mostly every text?

It means she's a middle school girl.

Stop texting and SPEAK to her. Have real conversations with her.

Texting misses the voice and meaning of most messages. Plus, messages can be misinterpreted.

I bet she giggles alot too -- like jespah says she is just being a middle school girl - they laugh and giggle alot and lol alot. Does she send little emoticons too? I wouldn't doubt it.

Just like middle school boys can be crazy (per my middle school daughter) - middle school girls act kind of silly cute - with giggling (that can drive sane people crazy) and cutie smiley faces.

Another thought as is said here - talk face to face with her. You will get more out of it. Alot of conversation is missed over non-face/non-verbal communication - body language and voice tone cannot be duplicated texting.

When you ask her what she's laughing at, does she reply "idk lol "

That would drive me nuts and make me want to slap the crap out of her.

Seriously though....because of being in middle school girl mode, she's probably having a hard time in either finding stuff to say, or how to say it.

Unfortunately, just like boys, she's concerned if you like her or not (while you're wondering if she likes you or not). Both of you are afraid to show feelings to each other. She's trying to figure out what you like, and has been led to believe boys like girls who are all silly and cute and say lol a lot.

Like others have said, you need to do some face time with her. Buy an extra soda and go to her and ask her if she'd like it. She'll be thrilled and will be telling all her friends how "HE BOUGHT ME A SODA!!! lol"