Grade
1

How Many Are Hidden? Shells

What do you notice? How many shells do you see?

A double-flap card showing 3 rows of shells. 3 in the top row. 1 in the middle. 3 in the bottom row.

There are 10 shells in all above. Some of the shells are hiding behind the flap. How many are hidden? Use math words, numbers, or pictures to explain how you know.

Challenge

Which equations match the picture card? How do you know?

A double-flap card. Under 1 flap, 3 rows of shells. 3 in the top row. 1 in the middle. 3 in the bottom row. Under the other flap, 3 more shells. The equations: 10 minus 5 equals 5. 7 plus 3 equals 10. 3 plus 7 equals 10. 10 minus 3 equals 7.

Follow-up

Tell or write a story problem that matches the picture card. What equation can be used to solve it?

Printable Version

Google doc for printing and copying

Reference for Educators

Sample problems and solutions