That quote, is SPOT ON! I don't disagree in the least. (Bet you didn't expect that, did you??) However, I don't know any elementary school students who are sent to the grocery store to do the weekly shopping on a budget alone. Number lines, hundreds boards, ten frames, algebra tiles, and all the other physical representations of math and numbers give students something concrete to set the stage for learning. We move away from each of them fairly quickly as students become more fluent in their math facts, but they provide a perfect physical and visual reminder for students to mentally refer back to as they learn and grow. We all encourage our kids to try new things - consider adding new math strategies to that list! (And cheer them on, just like you would if they were trying a new sport or instrument.)