There is a lot of good information here and more towards bottom - many information links that may apply....
Power Availability Requests - Manage in Windows
http://www.eightforums.com/tutorials/32947-power-availability-requests-manage-windows.htmlI would definitely NOT recommend any type Command Prompts or Power Shell commands to Force the Sleep or Hibernate tasks. This could possibly damage drivers. All that makes sense is to not have videos or movies running at the time of Sleep command. If this is a Parent Control type measure of forcing the child's pc off at a certain time no matter what is going on - I would recommend don't do it. You may damage the drivers involved.