I learned several things - create a behavior contract for the students. One student made potions, became invisible and started griefing (destroying the other player's works). (I did not even know you could become invisible!) Conversations were had and that stopped, but I want to make a formal declaration of the rules and consequences and have them sign it. Second lesson - probably best to have a planned world to demo.
Now on to other things. One of the seventh grade science teachers and I are brainstorming how to use MC for the digestive system. There are several videos of such projects online and I have downloaded one digestive tract world from Planet Minecraft. The question is - have each student or pairs of students each create a digestive system or have one they just go through? We will be discussing intent of the lesson and the amount of time to be allocated, as well as pros and cons of each method. (I don't want to see anyone's projects destroyed.) Also next week is a load test - we are bringing in several math classes to test how many people we can get onto our little server. We are planning to create something similar to decimal island for the kids to try.
On a personal note, I have learned how to install mods and where to get them. The wiki seems to be the go to place. I tried a commercial site the kids told me about and along came other ad programs.