not an advice but if i was in your place i would talk to her on the last week of the class or so, assuming there will be a last week and it's not something that will just go on indefinitely.

if the class is just going to be going on forever then you can't be as blunt - you would have to just casually get to know her to see if something could be arranged or not without actually suggesting anything.

but if it's like the last day you have a lot less to lose you can say anything as long as it's not insulting ( or she could have some White Knight Orbiter beat the shit out of you ). you can at that point just tell her that you want to ask her out, and if she says no you can say you will pay her to have sex with you just once - if you can make that offer without making her feel like a prostitute she will probably accept - women like sex and they like money - but they must have some kind of excuse where it doesn't make them a prostitute. same as how i need an excuse when drinking so it doesn't make me an alcoholic. if you can argue that you're not making that offer because you think she's a hoe, but because you want to remember her better she can say no of course, but it is doubtful that she will sic her BF on you to kick your ass ... UNLESS she is a sadist, but again, that's why you do it on the last day to reduce the odds that you will end up paying the price.

i talked to my crush in college on the last day and she said she had a BF ... she did it while touching my hand for no reason ... weird

then one time i called that Jewish girl that i was friends with from work and said i was horny and would pay for sex and she said i should come over and she'll do it for free ...

the point is if you do nothing - nothing happens. if you do raise the subject then something may or may not happen. but you want to do so in such a way that you don't get your ass kicked ( which has definitely happened as well on several occasions ) but more importantly ( to me ) you don't want to make things awkward for yourself like for example if it turns out some guy in the class is her BF and she tells him about your offer and then the 3 of you still have to come to that class every week LOL

it's just my rule is i don't do anything with girls from my school, my office, my gym, my building etc. i will only ever speak to a woman if seeing her again would be MY CHOICE. if things go south and i still have to see her every week that's a big no-no for ME.

this is why girls go on vacations so much - that way they can fuck with no strings attached. they WANT to fuck, they just don't want to feel shamed for it or become entangled in something. they hate needy guys. they want "romance" - which means getting banged by random strangers on some tropical island and then showing their BF at home pictures of the turtles on the beach.