3-Digit/Three-Digit/Triple Digit Addition Practice: Expanded Form Strategy
"Add Across, Then Down" Expanded Form strategy for adding three-digit numbers based on place value. Supports Common Core standards 2.NBT.5 and 3.NBT.2, addition within 1000 based on place value strategies.
This strategy requires students to first expand the numbers in a 3-digit addition problem into place value charts, then asks them to add across the rows of the charts to arrive at the total number of hundreds, tens, and ones in the equation. Students then add down the place value chart to arrive at the correct sum. This strategy highlights place value & number sense knowledge as a strategy for solving 3-digit addition. This strategy will prove very valuable in developing mental math strategies!
Packet contents include:
Strategy Posters: Illustrates the 3 steps in the Add Across, Then Down strategy: Color and B&W versions.
Strategy Slips: Smaller versions of the strategy posters. Perfect for attaching to homework, sending home to parents, or for gluing in interactive math notebooks or learning journals.
8 Practice Sheets: Scaffolded, guided practice with the Add Across, Then Down strategy. Practice pages are perfect for morning work, centers, homework, assessment, or intervention practice for students still struggling with 3-digit addition.
Answer Key included!