What are you like at multiplications? Chances are if you're a mere mortal 2, 5s and 10s won't seem too taxing. But when it comes to figuring out what 42x21 is, you may wish somebody had shown you the ...
Students in some local elementary schools are learning a completely different way of doing multiplication. It’s a technique that many parents can’t understand. It’s called lattice multiplication. The ...
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