Un-Mastering Skills?

My son has flown through the Early Math mission and has technically "Mastered" all the skills, yet still can't tell me what a rhombus is or easily solve the place value questions. Now he's moved on to 3rd grade math (his grade), and is "Mastering" the multiplication tables, without ever really learning them. Is there a way for me to Un-Master him at these skills, or re-incorporate them into his mission and daily work until he's truly learned them?

I've figured out how to go in and have him Practice the skills from the main page, but I was hoping for an area where he sees what he needs to do each day (for example: Today you need to practice 5 3-digit place value questions, 20 Multiply by 2, 20 Multiply by 3, and start 2 new skills)