So what I am looking for, is a way to override the device lock.
So, 2 different cases....
First - if I child has lost the privilege of using his/her device, we can force lock it for a defined time period. Essentially saying the child cant use it for the next '3 days' (or hours, weeks, etc)
Second - If a child has a need to use a device during normal 'locked' time (to finish homework, as a reward, etc) Basically unlocking for a one time use for a defined time period. Again, saying the child CAN use it for the next '3 hours' (weeks, days, etc) regardless of the normal schedule.
Once the time is up, revert to normal for each.
I know this appears like I am looking for a way to avoid just physically taking the device away, but we are trying to come up with a method to store the children tablets in their bedrooms, thus keeping them safe from their siblings. Plus, its kind of hard to take away a computer that's mounted in their office space. Adding this feature I have listed above, would solve the issue, and make things much more streamlined.