I'm always hesitant to do things like this because you're paid with a 1099 instead of a W2. I have never been a 1099 employee, but my understanding is that it makes taxes somewhat more complicated.
Fwiw, many school districts will hire substitute teachers who possess any bachelor's degree. They typically pay by the day. Schools near me average $80-$100 per day. I have only superficially looked into it, so Idk if these are W2 positions or what. I'd assume so, but I am not sure.