Check the replay menu (top right button of the main map) to see what you missing. You can have sex with miss Newman in the shower on a Thursday if you teach a sports lesson in the afternoon. You'll need to be at certain point in Sally's questline and you need to have found her missing keys.
There's a photo up there which looks like the girls in the shower stalls of the men's changing room. The one with Debbie up front? I haven't seen that in-game.
oh easy. she showers in the locker room on Thursdays. Go and do sports enough times and you'll come across her. eventually you can shower with her then fuck her.
