[ndriscoll]

It sounds like everyone in the class can clearly see what's going on, which means there's probably not a lot of "tutoring" going on in these 1:1 sessions. So no need for the other girls to worry much about that. That said, even if they were I'm not seeing the problem. If two people start dating is one not allowed to help the other with homework now because it's "unfair" to single people? I helped my wife (then girlfriend) with her work in college. In fact I helped her in her 1 semester general optics course in the physics department when one of my majors was optical science, so almost the exact same situation (though we met in a math class). Should I have offered to help her classmates too? Does it make a difference that she's older than me? Or that the other students didn't know I was giving her 1:1 attention?

I get that rejection is demoralizing. Probably almost any man understands that. But we can't exactly expect people to prioritize fairness to everyone in their personal relationships, nor does it make sense to ban students from seeking those relationships.