Area Wheel: Using a "story wheel" have students create their own math resource for area - include area of triangle, rectangle, parallelogram, and circle. Perhaps this could be modified to be a better fit.
It adds more rigor if students create their own equations and develop their own design. Have students create a certain number of each type of line, have them identify slope, y-intercept, etc. to cover more of what I am teaching on the concept.