I would call this a Level I activity, as the scale of the graph is always 1.
Riddles are a great way to make a boring worksheet fun. However, I found students knew the answer to the riddle and just chose the answers to fill in the letters without doing any of the math. This way, students have to create the riddle before they can answer it.
Also available in the finding slope riddle bundle
* Perfect for centers, homework or independent/group practice
* Engaging activity for students to practic