LOGICAL THINKING - Grade 2

Lesson 9 of 9

Activity 1

I will use  symbols and critical thinking to decode a message.

Read this story aloud:

Randy Raccoon at the base of his tree, scratching his head. In front of him lay a piece of paper covered with strange symbols. “Hmm… this isn’t any language I know,” he muttered.

Detective Daisy Duck waddled over, her magnifying glass glinting in the sunlight. “A secret code, Randy! Someone doesn’t want just anyone reading this!”

Randy’s eyes widened. “A secret code? Like spies use?”

Daisy smiled. “Exactly. It’s called cryptography—the art of using codes and ciphers to keep information secret. People have been doing it for thousands of years!”

Randy leaned forward, curious. “Thousands of years? How far back are we talking?”

Daisy nodded. “Way back! The oldest record we know of comes from Mesopotamia—around 1500 BC. Archaeologists found a clay tablet with an encrypted recipe for pottery glaze. Whoever made it didn’t want anyone else to steal the secret formula!”

Randy grinned. “Even ancient raccoons must’ve loved keeping secrets!”

Daisy laughed. “And Hebrew scholars, around 500 or 600 BC, used something called a substitution cipher—where one letter is swapped for another. It was a clever way to hide messages without anyone else understanding.”

Randy scratched his chin. “So… it’s like writing a message only your friends can read!”

“Exactly!” Daisy said. “That’s the heart of cryptography.”

Daisy pulled out an old photo from her detective notebook. “Now, cryptography became very important during wartime.”

Randy peered at the picture. “Who are those people?”

“They were Navajo Code Talkers,” Daisy explained. “During World War II, the U.S. military trained Navajo speakers to create a secret code based on their language. It was so complicated that enemies couldn’t break it!”

Randy’s eyes grew wide. “So, their language became the code?”

“That’s right,” said Daisy. “They helped send secret messages safely across battlefields. Without them, many missions might have failed.”

“That’s amazing,” Randy whispered. “A code built from words that already existed—but only some people could understand.”

Randy tapped the paper on the desk again. “So, if I wanted to make my own code, how could I start?”

Daisy grinned. “Try a substitution cipher! For example, you can shift every letter one place forward—A becomes B, B becomes C, and so on.”

Randy grabbed a pencil. “Got it! ‘Raccoon’ becomes… ‘Sbddppo!’”

“Perfect!” Daisy laughed. “You’re officially a cryptographer.”

Randy beamed. “Thanks, Detective! I never knew secret codes had such a long history.”

“Remember,” Daisy said with a wink, “cryptography isn’t just about hiding secrets—it’s about keeping important information safe. Now, let’s see if we can crack the message that started all this!”

And together, Randy and Daisy leaned over the mysterious note, ready to solve their next big mystery—one cipher at a time.

Activity 2

🔐 The Secret Code Key

A-    B H-    I O-    P X-    Y

B-    C I-     J P-    Q Y-    Z

C-   D J-     K Q-    R Z-    A

D-    E  K-     L S-    T

E-    F L-     M T-    U

F-    G M-     N U-    V

G-    H N-     O W-    X

Let's try this message:

Npstf dpef vtft eput, ebtift, boe tqbdft.

_ _ _ _ _   _ _ _ _   _ _ _ _   _ _ _ _,  _ _ _ _ _ _,   _ _ _   

_ _ _ _ _ _.  

Activity 3

Morse code uses dots, dashes and spaces to represent letters numbers and symbols. You can write Morse code, or send it with flashes of light or sounds. Once a prisoner of war even sent a message in Morse code by blinking his eyes!

Check out Morse Code.  Try sending Morse code messages with sounds, or actions (such as a flashing light), as well as writing it down.

Using Morse Code, figure out what this says:

• —    • — • •    • — —    • —    — • — —    • • •             — • • •    •             — • —    • •    — •    — • •              —    — — —         

— — —     —     • • • •    •    • — •    • • •

Free download for Morse Code:  https://picklebums.com/secret-codes-for-kids/

Activity 4

Create your own code.

Free download:  https://picklebums.com/secret-codes-for-kids/

Answers:

1. Story generated by AI.

2. Morse code uses dots, dashes and spaces. 

3.  Always be kind to others.

Source:  https://picklebums.com/secret-codes-for-kids/