Last year our good friend Ben Cahill posted a blog showing some of the best results from his students when using Playdoh to craft aggregate supply and demand diagrams! Here is the link as a reminder. Today I tried the same with an A2 group and set them two challenges. First to draw a cost and revenue diagram when marginal cost is low and constant and where demand is price inelastic. Second to consider a change in business objectives from profit to revenue maximisation with standard short run cost curves. All you will need for this activity is a plentiful supply of flexi-sticks (you can bulk buy these for an extraordinarily low price from Amazon), some scissors and a batch of mini whiteboards and pens. Here are some of the results. It is interesting to see how students approach this - it is a great way of isolating some common errors when drawing these theory of the firm diagrams and you can easily take photos of the best (and the less successful) for student folders and displays!Has anyone else used these flexi-sticks in the classroom? I can see them working well with AD-AS diagrams, market failure, different types of intervention in markets!