Problem solving comes FIRST, not at the end of the lesson or at the end of the homework.
What is a problem? If the mathematical task is has an obvious method to a single solution, then it is simply an exercise. A real problem has no obvious method and requires trial and error, defining assumptions, and identifying constraints.
Use chart paper to present your activity to the class. Define any assumptions,
identify any constraints, explain your thinking strategies and methods,
and justify your solutions.