No homework

I made a teen and she spawned on a Sunday as normal. I didn't feel like she should have to do homework on the very first day and on a Sunday so I just sold it. Now I assumed she would get a new one when she came home from school on Monday. But she didn't. Now she can never do her homework and after a week she is barely hanging on to a C. Now, is there a way I can get her homework back. I didn't mean for it to permanently go away. And what happens is her grades drop too low and what is too low?