This is Arrays and Random Numbers, from Week 5: Lists and Transforms.
We'll often walk through programs together, discussing each interesting or new idea. Because this is from Week 5, you'll already be very comfortable with most of the programming techniques I'm using here.
As always, you get all the programs in this video. You can then run them yourself, study them, play with them, adapt them, and use bits and pieces of them in your own projects.