Learning encryption

I guess I can talk about this now.  I suspect that the Statute of Limitations has run out.

In elementary school, it was very common for us to pass notes to friends in class.  Of course, they’d be written in code lest they fall into the wrong hands.

By today’s standards, it wasn’t very sophisticated.  I remember one where we just shifted the letters of the alphabet a number of characters.

So, a simple shift of one letter makes




I can also recall missing a couple of recesses as I learned this technique.   

But, little did I know that I was practicing for a unit later in life on code/code breaking and studying the classics like Alan Turing.

It seems so primitive now.  

It just got a whole lot more modern and fun with Mozilla’s Codemoji.

It’s not a tool for serious coding/decoding but a part of learning about encryption that brings it to a level that makes it easy for students to understand in a fun way.

The concept is fairly simple.  Type your message and encode it with an emoji and then send the link to your encryped message to your friend.  

Once they have the link, they can decode your message – provided they have the key to unlock it.  In this case, the key is an emoji.  

Now, the technique isn’t going to stand up to any level of cipher testing.  There are only a limited number of keys for the decoding.  However, it’s more than enough to cover the concept of coding and decoding a message.  There’s a level of satisfaction in decoding the message.  (There also is a certain level of trying incorrect keys!)

In the Computer Science classroom, of course, the next step is to write your own system.  I found that this was a fun activity for students.  In its simplest, we just did an alphabetic shift of # letters and wrapped from Z to A if needed.  That was enough for the basic program.

But, if you’ve ever taught Computer Science, you know that wasn’t enough for the hot shots.  They’d do things like making the shift go backwards, or go progressively through the alphabet (1 letter shift, 2 letter shift, etc.), use numbers, special characters, …  It was one of those activities that spurred on even more ideas.  

If you’re teaching encryption or about encryption, then you’ll want to poke around with this and then tuck it away for use.  The Mozilla page about Learning Encryption goes along nicely so bookmark it too.


OTR Links 06/30/2016

Posted from Diigo. The rest of my favorite links are here.