School tablets parental control

My brother (14) and sister (12) are required to have tablets for school. The tablets are connected to the smartboard when they're at school and they have all the assignments and books. They have Samsung galaxy tab S4. They are using the tablets for anything other than studying. They have to leave their cellphones out of their rooms while studying, but that can't be applied with the tablets as they have to study on them. Our mom wants to restrict the tablets so they're only for studying. the app lock apps aren't effective as they don't lock the browser and they are easy to bypass ( they delete the app ). Is there a way to restrict or at least monitor usage ( they'd know that we will know if they're not studying ). via /r/Parenting https://ift.tt/2Wii2Af