This kinesthetic activity involves students acting out various parts of the Internet including websites, routers, servers, and clients. It starts by examining swtiching networks (e.g. telephone systems) before looking at routing networks such as the Internet.
This is quite a complex activity which requires some preparation and setting up, but when this is done it is an excellent way to help students understand these topics. Thorough instructions are given in three blog posts linked from the CSE4K12 page. It is also possible to vary the difficulty level by including fewer aspects, making it suitable for students of different age groups.
This activity was created for Computer Science & Engineering for K-12 by Gary Kacmarcik, and is licensed as Creative Commons Attribution-Share Alike.
This video goes into a LOT of detail about DNS and the different types of nameservers: the root nameservers, the TLD nameservers, and authoriative name servers. This is probably more detail than most students will need, but it can help understand the bigger picture, so is included here.
This video explains compression techniques in the context of images. It is recommended that students have an understanding of how image data is stored (e.g. bit depths) before watching this video. The video is very comprehensive and so it may take a couple of viewings to fully understand the details of the examples being presented, but it is worth it.