Multiplication and Division Facts to 100

By Grade 6, multiplication and division facts to 100 should be moving toward automatic recall. The double-double strategy is one of the most efficient: 23 x 4 = double(23) x 2 = 46 x 2 = 92. This works because 4 = 2 x 2, so multiplying by 4 is equivalent to doubling twice. The strategy extends: x8 = double three times; x16 = double four times. Students with strategy-based fluency can compute any product mentally, not just facts they memorized.