Reading and Writing in ASCII

Passing Notes

How many times have your teachers told you or your classmates, “Don’t pass notes in class!” Well, now it’s your turn to do just that, but there are a few caveats:

  • Your note must be written in binary code (0s and 1s).
  • You must use the values for alphanumeric symbols found in the ASCII table.
  • You may not use any online alphanumeric/ASCII converters.

*A copy of the ASCII table is available at the end of these instructions.


  1. Match up with a partner.
  2. Write down the contents of your note in alphanumeric characters (e.g., “If there’s a bustle in your hedgerow, don’t be alarmed now.”)
  3. Use the ASCII table to write the note out to your partner using only binary code.
  4. When you have both completed writing your notes in binary, trade papers and translate the binary code back to alphanumerics using the ASCII table.

Think About It

  • Was there any noise in your partner’s note?
  • How do you know when one character ends and the other begins?