Create a monster!
This is such a simple and fun idea that can be used to kick-start imaginations for a huge variety of topics. I have used this method before when creating picture inspired by Miro and it helped the children include a full range of lines and shapes that they may not have other-wise thought of using. For slightly younger children though, I love this monster themed one! It also involves a bit of numeracy with the dice throwing and some motor-skills work as they try to copy the shapes. Great fun and great learning!