In World War II, Diné (Navajo) Marines built a code on the Navajo language and sent radio messages in it across the Pacific. The first 29 recruits created the code in 1942, and hundreds of Navajo code talkers served by the end of the war; the code was never broken. They were not the only ones: Choctaw soldiers first sent messages in their language in World War I, and Comanche, Meskwaki and code talkers of more than a dozen other nations served in World War II. Their work was kept secret for years after the war. The codes on these pages are our own simple number codes for practicing math. They use no Navajo words and are not the Code Talkers' code, which was built on a language, not on numbers. Facts are from the National WWII Museum, the National Park Service and the Smithsonian's National Museum of the American Indian.
Five pages of 2nd and 3rd grade number codes. Page 1 tells the Code Talkers' story in a few lines, then decodes four nature words: solve each fact, then find its letter in the code A = 1 to Z = 26. Page 2 encodes eight words. Page 3 has four shift codes: fill in each code table, write its rule, and decode a word. Page 4 adds up the numbers of six words, then finds the secret word by its sum and the word with the greatest sum. Page 5 finishes a doubling code by counting by 2s, then decodes three words and encodes two. The first problem on each page is a worked example.
Read page 1's panel aloud before anything else, and talk about why a code built on a language that few outsiders spoke was so hard to break. Make clear that the number codes here are a game for math, not the real code. Then let partners send each other messages in the shift codes of page 3.
Write a short message in the A = 1 code for your child to decode at breakfast, then let them send one back in a shift code with a secret rule.
This pack supports the following Common Core State Standards for Mathematics:
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Number codes made in honor of the Diné (Navajo) Code Talkers of World War II, whose code was built on the Navajo language and never broken; the codes on these pages are our own. Students solve facts to decode messages, encode words, find the rule of a shift code, add up secret words and count by 2s in a doubling code.
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