You can't teach her. She has to learn. There is no greater teacher than experience.
She is doing what many kids do the first time they have "real" money - she spends it.
Yes, she can get student loans and perhaps some scholarships, although th scholarship funds are lower than she thinks. She may be a great student, but she will quickly find that everyone at her desired college(s) is a similarly gifted student - they are a dime a dozen. It's a rude awakening for many college kids.
You have been honest with her. I would stop talking about it, and give her something written with the available funds listed. Then put on the same page the cost of her tuition, room, board, books, laundry, "extras" and entertainment. Have her do a budget - if it's at her leisure, that's her business. If she winds up at community college because she can't find $30K a year, so be it. Every college can give an estimate of what all the fees are, but have her include "luxury" things like going to the snack bar for a coffee, paying for laundromat fees, buying college tee shirts and other spirit wear, and tickets to the comedy show or the football game. Then she can figure out how much she needs to save from her part time job.
You can also have her pay her application fees - that's a start. She'll have to choose the best matches for her because she won't have enough money to apply to 25 schools.
You can also require her to fill out the FAFSA form herself - that's pretty awakening and enlightening. That will require you to give her income info though, but you can have her do a portion of it and list how much she plans to pay for her own education.
If she winds up blowing all her money and having to take a year off before going to college, is that the worst thing in the world? No. Kids rally all the time, and many take a "gap year" on purpose. She may take one by default.
I'd stop talking at this point, and I'd write it all down of what you are contributing and what she needs to make up on her own. Have her sign that she has read it, and then you each keep a copy. It's a kind of a contract. Then she can't come back to you in 3 or 6 or 9 months and say she didn't know.
It would be nice if she could talk to a few recent graduates who have $40K or $200K in debt, to tell her how they are really struggling and still living with Mom and Dad because they can't afford an apartment and their loans on $60K salary a year - then she can figure out what it's like for all the grads who don't have a job or one that pays close to $60K a year. But a lot of what has to happen here is just reality and maturity. You can't rush that, I'm afraid.
This is also a good time to sit down with the other kids to lay the groundwork for them as well.