Warm-up Number Talk: 10 and Some More
Find the value of each sum mentally.
Activity 1 Shell Collections
Diego has 55 shells. Lin has 20 fewer shells than Diego.
Use the story problem to complete the diagram.
Write an equation to show how you could find the unknown number of shells. Use a question mark to represent the unknown.
Activity 2 Card Sort: At the Beach
Read a card with a story problem.
Find cards that match the story problem.
Explain why the cards match.
There are 25 crickets chirping in the front yard.
There are 16 fewer crickets chirping in the front yard than in the back yard.
Label the rectangles to match the story. Explain your reasoning.
Write an equation to represent the story problem.