Finally, it all adds up. Learners complete a number puzzle in which they investigate the sums of the digits one through nine in a cross pattern. They then try to determine what totals are possible and which ones are not before devising a proof showing they have them all.

Concepts

addition, proofs, linear equations, totals, math puzzles, number puzzles

Show More Show Less

Additional Tags

math

Show More Show Less

Instructional Ideas

• Have pupils discuss why an even number does not work in the center
• Get individuals to share their strategies

Classroom Considerations

• Some learners may get frustrated by going through all the possibilities to determine the totals

Pros

• Task is one step in the process to achieve the CCSS Math Practices
• The activity is open and allows for multiple access points

Cons

• None

Common Core

MP2 MP3 MP6 MP7