1. Start off by getting students to think about how they walk by breaking down the action into small steps and thinking about balance and whether they shift their body weight to a specific side

2. Can students program their friends to take one step forwards using only the instructions given in their workbooks/slides?

3. Moving into small groups with a device and a Marty, get students to try and translate the instructions they just gave each other to get Marty to take one step forwards with his right leg

4. Then again with his left leg

5. Ask students whether they can use something to stop repeating the blocks for each left and right step

a. Functions! Students should create two functions: one for stepping with the right leg and one for stepping with the left leg

6. Then create a loop that calls both of these, but do students notice how many steps Marty takes per loop or iteration?

a. He currently should be taking two steps each time we go around the loop but what if we only want to take 1 step? We need to keep track of the last foot we stepped with

b. Using a variable, each time we call step left or step right, update the variable to hold either “left” or “right” and check to decide which function should be called

c. Place this code in a function called step

d. Then whenever we call step in our main sequence of blocks, we will be able to get just one step!