Below is a gallery of different blocks that can expand your current block library. For the castle assignment use the techniques you practiced and create at least 3 extra blocks either of your own design or from references you find here or online. Then create a large arrangement that represents your own amazing castle.
Optional Videos* Below are Addendum Videos to help with the project curve on mesh, and the Mug Lab; these are not assignments!
Project Curve Broke? Try this Old School Method
I got a few emails about Project Curve on Mesh and Split Mesh with Projected Curve so I made a second short video of the process. If your Maya is not letting you do this, then perhaps the tool in the version you are using is broke (but I can't be sure of that).