All,
Tomorrow I will be doing a 30 minute presentation to second grade classrooms by request as a follow-up to career day. One of the key components requested was to involve the students and have them build something hands on. At the last minute, I was told that the computer lab was no longer available as I was going to have them build a small program in Scratch.

I am still going to use the classroom computer with overhead projector for most of the presentation to include showing off Scratch. I am struggling with what to do with the hands on portion (approximately 10 minutes).

One idea I have is for them perform a bubble sort based on their heights. I am concerned about time as well as individuals moving when it is not their turn to swap.

Another idea I had would be for them to do something like a Caesar Cipher where they reveal a secret message by following a simple algorithm (pen and paper).

My OT question to you is: If you had around 10 minutes to give second grade students a hint at computer programming without them having access to a computer, what would you do?

Update: It was a smashing success. I had 30 minutes per class with 5 classes total. The format was as follows:

1. Short presentation
   1. Why we are here (S.T.E.A.M School = Science, Technology, Engineering Arts and Mathematics)
   2. What I will be talking about = Computer/Software Engineering
   3. What makes a good engineer (math, problem solving, creative thinking, curiosity, etc)
2. Short Scratch demonstration where I built a program live in front of them (rocket ship that chases the mouse around the screen with an outerspace background and plays a "ray-gun" sound when it catches it
3. Sandwich demonstration (just jelly since I was concerned about potential allergies).
4. Live bubble sort demonstration
5. Question and Answers
6. Caesar Cipher and Binary Search homework

Now, you are probably thinking how did I cram all of that in 30 minutes with second graders. First, for the Sandwich demonstration I explained that they would be programming me but that if they were loud and disruptive, the program would get confused and crash. Second, I told them that they could only provide an instruction if they raised their hands and the teacher called on them. No one completed a sandwich. For the bubble sort, I had the teacher select 5 to 6 students and had them line up single file. I used an eraser as a token to indicate who was in conrol of determining swaps. I had them each hold a piece of paper with a very large digit 1 - 9 on it. I feel kind of bad about the Caesar Cipher homework though - the secret message that they needed to reveal was "this was fun". Reminds me of the movie A Christmas Story and being reminded to drink Ovaltine.