An icebreaker is an activity that gets the blood pumping, forms connections between learners, and introduces a topic. There are thousands of different ways to introduce a topic and get learners interacting with each other. Choose one of these and hack it to be your own!
A Diving In activity is one that gives pointed instruction to participants on tools or procedures. An example of a Diving In activity would be allowing the participants to get used to the interface of Thimble or Popcorn by having them make projects. Before learners can practically apply new skills, they need to be comfortable with the tools they'll be using and have a basic understanding of the skills they'll be sharpening.
A Hands on Hacking activity is a practical activity that allows learners to delve deeper into the essential questions of your session. Go back to thinking of the results: what will your learners MAKE when they are done? Create a project that gives learners enough time to explore and tinker while working towards the completion of the activity.