Are multiplication and long division by hand really necessary skills? I never need to "fall back" to the principles of multiplication. Multiplying by the 1s co

Are multiplication and long division by hand really necessary skills? I never need to "fall back" to the principles of multiplication. Multiplying by the 1s column, then the 10s, then the 100s feels more like a mental math trick (like the digits of multiples of 9 adding to 9) than a real foundational concept.