Buddy, to figure out whether she likes you or not is easily to be noticed by eye contact. Try to look at her during class, if she stares at you look her in the eyes for a second and then turn your head back to where it was. Then after 5 seconds look at her again, if she's looking you in the eyes (right again) you should KNOW that she is interested in you.
Once you figure out whether this applies, man, go talk to her. I mean, girls love confidence and honestly, you must be. Alpha vs Beta, thats how this system works. Ask her out, don't be shy! Life is too short to wait with oppertunities like these. Before you know it, your chance will slip away and you'll have a lifetime regret.
When things don't work out as planned, it will obviously hurt you a lot- but thats a nice thing; thats when you know that you should move on and accept that it won't work. Don't waste time, or wait too long in life man! All in all, I can't estimate this whole situation but all I can tell you is don't wait too long, be confident, take her out. You don't need to show her that you really like her, just try to spend time with her and if it clicks, things will eventually evolve

Goodluck buddy!
Clyze
EDIT: Oh and PS, a job? Sure a job will help, but I mean, you're both in the 17-19 range. Thats when a job is pretty good, but not essential for relationships. Go and give it a try, you'll do just fine. I am sure

wow! thanks for this! You sure speak like one that is mature of handling relationships. Thank you buddy.! I am uplifted