Multi-Digit  Multiplication

Just as knowing the single-digit times tables saves work over adding the same number over and over again, the procedure for multi-digit multiplication saves a lot of work over, for example, adding 91 25 times.

Talking students through the process using the rows by columns format helps them see the reasons for the carries, indenting and subtotals.

In an era of calculators, some might argue that you can skip learning computation altogether. However, while learning rote computation doesn't do much good, learning the reasons behind the procedures provides a foundation in reasoning that will carry over to higher level math, science and other fields.