Multiplication (whole numbers)

Multiplication (by 3+ digits)

We discuss the algorithm for multiplying multi-digit numbers in detail in the lesson Multiplication (2x2 digits).  Once you start working with longer numbers, the process continues:

Multiplication (2 by 2 digits)

The algorithm for multiplying a two-digit number by a one digit number is pretty simple: you multiply the one-digit number by both digits of the second number.  And, if you keep things lined up, your tens digit ends up in the tens column and your ones digit lands in the ones column, and your answer turns out perfect.

Multiplication (2 by 1 digit)

Times tables are great for multiplying one-digit (and select two-digit) numbers. But, once we get into larger numbers, it's important to understand how multiplication works when numbers have multiple digits.  We typically use a number of algorithms for doing multiplication -- namely we multiply all digits of multipliers by all digits of multiplicands.  The processes become automatic, but it's very helpful for students to understand why we have to multiply each digit by each each digit.

Multiplication (Times tables)

**Note: A huge part of learning times tables is practice.  Scroll down for a blank times table chartworksheets (40 and 100 problem sets), times table sprints (for competitive practice), and times table tesselations (for artistic practice).**

Multiplication is the process of adding groups, multiple times.  It's a streamlined and faster way to add, if you need to add the same number repeatedly.

$4+4+4+4+4=5 \times 4$