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CRACK THE CODE · GRADE 2

Unicorn Valley Cipher

Find the hidden number for each star, crown, and rainbow to crack the code and unlock the star-dust chest.

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

=7
=4
=6
=9
=3

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.+−=CODE 1
  3. 3.+−=
  4. 4.+2=CODE 2
  5. 5.3=
  6. 6.2+=CODE 3
  7. 7.2=
  8. 8.2+=CODE 4
  9. 9.?+=10Which shape?
  10. 10.+?=13Which 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 star-dust chest.

Show answer key (for grown-ups)

Key: triangle = 7 · pentagon = 4 · cross = 6 · moon = 9 · star = 3

Every symbol is a whole number from 1 to 10.

1.moon + pentagon13
2.triangle + cross - moon4
3.star + pentagon - cross1
4.pentagon + 2 x triangle18
5.3 x cross18
6.2 x cross + triangle19
7.2 x pentagon8
8.2 x moon + pentagon22
9.? + pentagon = 10cross
10.cross + ? = 13triangle

Vault code: 4892

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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