13) Missing Number Equations

Bonds of 5: Three in a Row, Fill a Row, Tic-Tac-Toe


Develop fluency using two-part bonds of 5 in related addition or subtraction equation where the unknown is a missing part.

Please Note: Please start with the ‘a little easier activities if students are unfamiliar seeing the missing number in a position other than the answer .


  • addition as ‘add’. Read aloud as “(Part) add (part) equals 5”.
  • subtraction as ‘subtract’. Read aloud as “(Whole) subtract (part) equals (part)”.
  • equals
  • subtraction solved using adding on. For example, 5 – ? = 3 can be thought of as “What part joins (adds on) to 3 to make the whole of 5?”

Please, click this link to read Teacher Notes for information about “Solving Missing Number Equations” using part-part-whole.


A little easier

A little harder


In the next activity students apply the skills of representing of Bonds of 5 with Bond Blocks and as addition and subtraction equations to create related number stories using words and pictures. Go to

Activity 14

Bonds of 5: Representing Addition, Thinkboard

Bonds of 5: Representing Subtraction, Thinkboard

NOTE: Do not go to Activity 13 Original. This is also a Missing Number Equation activity.