It would be my guess that the charge is overblown... and she indeed didn’t abuse them.
Seems to me that a mother who actually cares about her kid’s homework is not the type to abuse the same kids.
The father reported it and the kids admitted it to the police. You can say that a mother who cares about her kid’s homework isn’t the type to abuse them but that is wrong. People who physically abuse their kids can do it for all sorts of reasonings. I’ve seen it when I was a kid. A little girl showed up for school all black and blue. Her Mother had beaten her with a hanger... reddish purple lines all over her legs, arms, back. Why? Because of report card day. She got a C in math. I guess these two moms had something in common: both really cared about their kid’s education. /s