I spend an entire class period (I teach a CompTIA A+ class at a local community college) stepping through a PC powering on, DHCPing, pinging the computer next to you, ARP (ARP Caching), DNSing (DNS Caching) and SMTPing an email to a POP server across a WAN. I go down and up the "TCP/IP stack" multiple times. It's exhausting and the students leave at the end of that class with glazed eyes. I get positive feedback every time I do it. I should video it and post it in here.
You should, the best way to learn this is by repetition and if you can cover the subject from different angles it helps to understand. Because you are a teacher you probably have a very good approach on the subject. 73 Pascal VA2PV
Have you ever considered a "problem centric" presentation or POV? Like "My internet service is down" THEN delve first into PING, TRACERT and deeper thereafter (DNS system, caching - all that you cover *but* from a problem solving aspect)?