This interactivity is designed for the problem Cushion Ball.
The interactive diagram below has two labelled points, A and B. What is the shortest path from A to B if you bounce off one cushion? In the diagram, you can click on the "Show" buttons to draw the four possible paths from A to B. Which is the shortest? You may move A and B around by clicking on them.
What is the shortest path from A to B using exactly two cushions? The interactive diagram below shows the eight possible paths from A to B. How would you calculate the shortest path?