Today we talked about something that is just a lot of fun to play around with - destructible meshes.
Step 1) Go to plugins (in the edit menu) and search for destruct and turn on all the plugins. (For me, I only had to turn on Apex.)
Step 2) Right click on a mesh, and choose "Create Destructible Mesh".
Steps 3 through 30) Play around with the settings until they work the way you like.
Step 4) Run it in the world and see them shatter!
We then talked about how to make blueprints interact with other blueprints and actors in the world. The easiest way is to make a variable, and set it as public, then recompile (don't forget to recompile - it won't appear until you do) and then back in the editor you can use the eyedrop tool or the search box to link some actor in the world to the blueprint. You can then have that blueprint mess around with it, such as by changing visibility, or giving it a physics impulse, or whatever.