This scratch project below shows four methods of sensing in Scratch can you find them all?
Challenge #1 – Create a NEW project using two sprites. Make something happen when the blue part of one sprite touches the Red part of a background. Hint: 
Challenge #2 – Remix the penguins project used in the example above. Have the penguin get closer to the ship before he is beamed aboard. Hint: it is a script on the space ship
At this point you can continue on our work on your Greek Myth game.
challenge #3 – Keep remixing the project so that he changes when he sits on a different chair. Hint: It has to do with when touching color
Challenge #4 – Construct an animation of two dogs who compete to get a bone. Initially, the dogs line up and wait for the cat to signal the start of the reach for the bone. The first dog to arrive at the bone picks it up and runs away with it. Ensure that one of the dogs runs faster than the other so that he will reach the bone first.