By monitoring your kids' accounts with Family Safety, you get a better sense of whether they're finishing their homework or spending too much time online. This info can help you set specific PC activity limits for each child, including when they're allowed to use the PC, what games and apps they can use, and which apps they can see in the Windows Store.
You can set and manage all these limits on the web, from anywhere. Just sign in to the Family Safety website, tap or click Edit settings for the child whose settings you want to change, and follow the instructions from there. Of course, you can also manage your family's settings on each of your family's individual PCs. For more info, see Set up your kids' accounts in Family Safety.