When I was younger, I had a friend whose dad would shut down their house's internet connection every 12AM without fail. He'd love Circle with Disney if his children were still kids. It's a cube (despite its name) that pairs up with your WiFi network and gives you the power to control your kids' internet activities. The device's creator, Jelani Memory, originally tried to raise funds via Kickstarter a couple of years ago, but the campaign didn't reach its goal. It turned out to be, as Memory told Wired, "a really great failure," because the startup found a powerful partner in Disney.
The device has an accompanying app you can use to limit the number of hours a particular child can spend on his/her phone or tablet. You can also use it to monitor the apps and content your kids are accessing on their devices, or (if you have to take drastic measures) even to block your house's WiFi connection. According to Memory, the system works by inspecting network packets from connected devices to determine if they have the permission to access the internet. The founder knows that the technique is typically used by black hat hackers for man-in-the-middle, but he pinky swears that its users' data "isn't sitting up in the cloud somewhere" for the company to mine or sell. Circle for Disney is available right now for $99, and thanks to its partnership with The Mouse, its MyCircle app comes with Disney videos and music kids can enjoy.