Skills Covered

How to Use This Worksheet

Count individual unit blocks and write the number. A visual introduction to ones within 20.

Tips for Success

• Use physical base-ten blocks alongside the worksheet
• Have students say the number in expanded form aloud
• Point out patterns in how tens and ones combine
• Check that students count each block type separately before combining

Common Core Standards Alignment

This worksheet supports the following Common Core State Standards for Mathematics:

• 1.NBT.B.2 - Understand that the two digits of a two-digit number represent amounts of tens and ones
• 2.NBT.A.1 - Understand that the three digits of a three-digit number represent hundreds, tens, and ones