2 Digit Addition Math Warm Up

Pull some starfish from your math wall (counting by 5 display) to use in a math warm up for 2 digit addition. Your students will add within 100 with using concrete materials to support them. 

skip counting by 5

Starfish Addition

  • use a selection of starfish that feature 2 digit numbers (e.g. 30-50)
  • provide counters and place value blocks for your students
  • cover all the numbers on 2 starfish
  • students take a counter from each starfish to reveal 2 numbers to add
  • students build the addition with place value blocks - e.g. 34+28
  • support students in place value concepts for addition - combining the ones then tens and trading where appropriate
2 digit addition with place value strategies


first grade math addition

Optional: ask your students to record each addition in their math journal or on a whiteboard with pictures of number sentences. If you're using this activity as a war, up you may prefer to focus on getting as many additions completed as possible and encouraging math talk to discuss the totals and findings. 

starfish counting by 5 display