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CRACK THE CODE · GRADE 2

The Championship Locker Code

Find the hidden number for each piece of soccer gear to solve the math equations and discover the locker combination.

Each shape stands for a number. Then solve the shape equations and read off the 4-digit code. Do it here or print the sheet — the answer key comes with it.

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The key

=9
=6
=7
=3
=2

Every symbol is a whole number from 1 to 10. A number in front of a shape means multiply: 2 stars = 2 x star.

Crack these

  1. 1.+=
  2. 2.2+2=CODE 1
  3. 3.++=
  4. 4.2−=CODE 2
  5. 5.2=
  6. 6.2−=CODE 3
  7. 7.3=
  8. 8.2+=CODE 4
  9. 9.+?=5Which shape?
  10. 10.+?=12Which shape?

The vault code

Take the ones digit of your answers to problems 2, 4, 6, 8 (the ones tagged CODE 1–4), in that order. That opens the team gear locker.

Show answer key (for grown-ups)

Key: triangle = 9 · moon = 6 · star = 7 · ring = 3 · lightning bolt = 2

Every symbol is a whole number from 1 to 10.

1.triangle + star16
2.2 x star + 2 x moon26
3.ring + moon + lightning bolt11
4.2 x lightning bolt - ring1
5.2 x ring6
6.2 x triangle - ring15
7.3 x triangle27
8.2 x lightning bolt + moon10
9.ring + ? = 5lightning bolt
10.triangle + ? = 12ring

Vault code: 6150

About Crack the Code

Crack the Code is early algebra without the letters: a key maps shapes to numbers, and the kid substitutes, computes, and — from grade 3 up — deduces hidden values from shape equations before they can solve anything. Grade 2 practices addition, subtraction, and multiplying by 2 and 3. Every sheet has exactly one right key and one right code.

It's one of three things Math Mysteries makes, free and printable, personalized to what your kid is into: a full math mystery whodunit, a Lab Work sheet of multi-step word problems, or a Crack the Code sheet like this one. Browse free printable worksheets by grade, skill, and theme.

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