I know you're being downvoted, but when I was young, my parents were able to turn off mobile data between set hours through our carrier (Verizon Wireless). It m

I know you're being downvoted, but when I was young, my parents were able to turn off mobile data between set hours through our carrier (Verizon Wireless). It might have required paid parental controls, but I don't think so. They claimed it was to make sure the phones didn't chew through our small datacaps at night in case things went down, but it had the effect you were looking for.