Take 7x6 for my example for upper elementary friends who are still mastering their facts. If I know 7x5 is 35 (since my 5s are easy!), then 7x6 is just one more 7. 35+7 = 42. Done. I didn't even need my ceiling tiles! This strategy, along with decomposing numbers, where we distribute a harder fact (like 7s) into easier facts. Using the 7x6 example, I know I can bust up the 7 into a 5 and a 2. Therefore I can take (5x6) and (2x6) and combine the results. 30+12 = 42. Still 42 no matter how you slice it! Again, number sense to the rescue!
For our older students, the problem becomes the numbers extend past 12x12. Middle schoolers often are faced with 17s and 19s, numbers beyond their experience set, so decomposing numbers down to their prime factors helps with reducing fractions, finding least common multiples and greatest common factors. Having full mastery of your multiplication facts will have a dramatic impact on algebra readiness and upper level courses.
High schoolers have even higher expectations of them and need this kind of stuff to be easy so they can conserve brain power for the problem solving.
Jo Boaler is an authority in the math community. I've taken a few online courses with her through Stanford and her perspective is right on with my thinking, which of course aligns with Mathnasium, the Mathnasium Method, and has been wildly successful with Mathnasium's Numerical Fluency program with our youngest learners. Building number sense impacts the student for the rest of their life and makes the always progressing subject of math an easier subject to understand.
Source: http://youcubed.org/teachers/
