Code Cracker Activity

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Updated on Feb 28, 2014

For a curious fourth grader, what could be more fun than secret codes, especially if they're connected to a tree fort, a secret rendezvous spot, or a special friendship? Turns out that secret code activities also represent great practice in language and reasoning for kids of all ages.  Any working code must rest on a pattern system which can be logically decoded. Our alphabet is just one such code; as a civilization we have chosen it to create an ordered, reliable way to communicate and connect.

So here are four secret code schemes we think are great fun for fourth graders. They are by no means the only ones, though! Do encourage your fourth grader to let his imagination soar. She may not realize it, but she'll also be building strong reasoning skills in the process.

What You Need:

  • Paper
  • Pencil
  • Imagination

What You Do:

Start by writing the 26 letters of our alphabet across the length of a plain sheet of paper.  This makes it easier to see the array that you’re working with; to make sense of most codes, your kids will need to keep this sequence firmly in mind.


Code 1: “Hop One.”  This is an easy code to write, but a surprisingly weird and challenging one to decode!  Just replace each letter with the one just after it in the alphabet.  “Read a book,” for example, would be “Sfbe a cppl.”  To make a “z”? Loop back to the start and write “a.”

Code 2: Capital Letters.  Write a short passage using lots of proper nouns and capitalized first words in sentences.  The message is composed by stringing only the capitals together.  “Eat good food,” for example,  would come from “Every time Arthur went to Total Goodness to eat Outrageous Orange Donuts, he ended up seeing his arch enemies, Fred, Oscar, Ozzy and Danny.”

Code 3: “Hieroglyphs.”  Ancient Egypt was just one of the cultures that used pictorial representations to create a language.  In this case, invite your child to design an original symbol of some kind to substitute for every letter of the alphabet.  If your child likes using computers, this can also be done by matching a font such as wingdings with a regular letter font.

Code 4: Word Weirdness.  Create a message with several words, and “hide them” in a set of sentences.  Each word in the message can only be found after a proper noun or a capitalized initial letter.  Here, for example, is  “Go south 8 yards”:  “Justin, go find out why Wayside Garden’s south gate, the one off I-8, seems to be opening into two Ivy Corner yards.”

Julie Williams, M.A. Education, taught middle and high school History and English for seventeen years. Since then, she has volunteered in elementary classrooms while raising her two sons and earning a master's in school administration. She has also been a leader in her local PTA.

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