Course A supplies--marbles needed?

When I finished my training, I received an email from code.org with a link to their lists of supplies on Amazon.com. It has marbles listed as being needed for Course A, but I went through all the lesson plans and didn’t see them. Did I miss them? What lesson uses marbles? I’m the coordinator of technology for my district and need to get supplies ordered and don’t know if we need these and how many. Thanks for your help!
Kimberly Karnes