While looking for other things (you know how that goes) I found a series of Office Mixes that teach how to program using TouchDevelop. They are mixed in as part of what looks like a more involved (though still basic) course. You can find the complete set in the Mixes loaded by Rane Johnson of Microsoft Research. This is the list of Mixes that specifically address TouchDevelop features though. I hope you find them useful.
TouchDevelop Programming This mix introduces you to the power of TouchDevelop, a versatile programming environment where you can make games, programs, and mobile apps in a simplified fashion.
Programming with Parameters In this stint of programming exercises, learn how parameters can be used to make functions reusable.
Variables, Conditions, & Loops This lesson gives an introduction to variables, loops, and conditional statements. Practice implementing them with TouchDevelop
Function+Abstraction Learn more about functions and how they are used to improve efficiency, organization, and happiness of code. Practice in TouchDevelop
If you are interested in Turtle graphics (and who isn’t) I have an introduction to Turtle graphics in TouchDevelop as well. I hope to have more TouchDevelop Office Mixes in the near future.