4.NBT.B.5 — Multiply Whole Numbers Using Place Value and Properties

Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.

Students learn to multiply larger whole numbers by a single digit accurately and efficiently. They should connect each step of the multiplication to place value, such as understanding what happens when multiplying hundreds, tens, and ones.

Students solve multiplication problems involving two factors that each have two digits. The focus is on breaking numbers apart into tens and ones and combining partial products in a meaningful way.

Students apply ideas such as the distributive property and place value to make multiplication strategies logical and understandable. They should see multiplication as combining groups of tens and ones rather than only following a procedure.

Students illustrate multiplication using equations, rectangular arrays, and area models to show how the numbers are composed. These visual representations help students understand why their strategies work and support accuracy.

Students communicate how they solved multiplication problems using words, pictures, and equations. This builds mathematical reasoning and helps them move from concrete models to more efficient abstract methods.