Very inspiring idea, I would say maybe the obsession of her to get him to improve is the main drive to get her to resort in to desperate acts.
Yes! A different female for each aspect of his development (math, history, fitness, science, etc.). She would basically coerce/negotiate with various women to help her son depending on the path. She is almost singularly motivated to have him succeed. Few examples I'm thinking of:
1. Female history teacher has unmet sexual needs and so mother can offer her son to fulfill them to guarantee she would tutor him/go easy on him in class. (or perhaps she offers his friend instead of her son if it's NTR route, based on how close she is to her son's friend).
2. Maybe there is a female college student who is really good at math and the mom can guarantee a job for her when she graduates. One thing leads to another and the tutor offers a "reward" to the son in exchange for him promising to study. (or the son's friend's dad owns a company who could hire her if she performs favors for him. Mom leverages this connection to ensure that the student tutors her son as well, maybe threatening to stop having sex with son's friend if he refuses. Son's friend requires college student to have sex with him in addition to helping tutor his friend. She begrudgingly accepts.)
3. Female fitness instructor needs a partner for tennis match and so mom can offer to be the partner in exchange for coaching her son (or mom can offer son's friend's help, since son's friend is great at tennis, etc.)
4. After enough of son's life areas are improved (grades, fitness, etc.) mom progressively falls for him and seduces him (though he harbors these feelings secretly). Alternately, son's friend is so helpful she falls for him instead.
5. Daughter/older sister becomes closer with her brother as he improves hoping to mooch off his success in the future, plus secretly finds him cute. As things escalate, she drunkenly makes moves on him. Mom allows this and views it as a positive influence on her daughter. Alternatively, son's friend is distracted by sister and makes moves on her over time. Instead of stopping it, mom allows it in order for her son to focus more on what's important instead of playing with friends or getting distracted by loser sister himself.
Already a lot of ideas here, but could set up situations with mom's boss (or mom's boss's daughter) to tutor a subject, neighbors, other teachers, professionals, or classmates, etc. Could also limit it to literally a few characters depending on your time/scope you want to dedicate to this (I'm not assuming you will do this idea at all, lol, but I think it'd be good and I'd definitely buy it, like I have with your others.)
You're one of the few makers who hits basically all the themes I like and has great animations with a smaller peen. I'll probably love your next work as well, regardless how much it resembles this idea. Keep up the great work!