This is the best 15 minutes of professional development in mathematics you are likely to get. It explains in detail the three different types of division models, using concrete examples, that you should be introducing to your third grade students, or reviewing with your 4th, 5th & 6th grade students.
It is incredibly important, because without this knowledge, your students will be unable to do the following:
• Solve a word problem (because the keyword approach is nonsense.)
• Divide fract