There is a code table at the top. Each letter has its own number there.
Work out a task and look up the result in the table.
The letter next to it goes in the box below the task.
Each row spells one word, and together they make a whole message.
Example: the table says E = 3.
The task 1 + 2 makes 3, so an E goes below it.
Tip: the task checks itself. If a row does not spell a readable word, one of the calculations went wrong.
Example
For parents
What does this exercise practice?
Calculating with a purpose. The result is not the answer but the key to the next step, and the message shows at once whether everything was right.
Common pitfalls
Children write the result number instead of the letter. It helps to do the first row together and say it out loud: first calculate, then look up, then write.
How to practice at home
Write each other secret messages. First agree on a small table, then encode your own name as calculations.
Related: Magic wand code, The Secret Code