At home networking and monitoring

I recently purchased a new iMac desktop computer. I am looking to set up an at home network with the desktop, my laptop, and my children's 2 laptops. I currently have the Server app as well as Remote Desktop which I would like to use to monitor my children activities. It's not that I don't trust them ... okay, I don't fully trust them. I would really like to be able to update and control all the laptops at once as well. I worked as a school technologist for 12 years but for some reason, I was able to do all this there but not at home.

Anybody have advice on how to do this? All the computers are running Yosemite. I am using a cable model through Brighthouse in Florida if that helps at all. I would be glad to furnish any additional information.