At Tapia Camps, we create original hands-on STEM activities that are relevant to the lives of our campers.  We are excited to share one of these activities with you now.  All you need is a printer, some scissors, and about 45 minutes.  This activity is about hiding secret messages in computer images, which is important because of recent advances in artificial intelligence (AI).  It is meant for middle and high school students, and it helps build skills in computational thinking.

Using AI, ordinary people can make realistic images of things that never happened. As a result, it can be hard to know if you should trust the images you see. To help people detect AI-generated images, engineers at companies sometimes place a secret message, known as a watermark, inside AI-generated images. These watermarks are not noticeable when a person sees the image, but a computer can typically detect them unless the image has been further altered. 

In this activity, you will assemble an image by hand using squares of various shades of gray.  Then you will follow some simple directions to reveal a secret message.  After that, you will choose your own secret message and learn how to hide it in an image.  If you enjoyed doing this, consider coming to Tapia Camps.  There you’ll get the chance to experience other hands-on activities across many areas of STEM, including computational thinking.  

To complete the activity, download and print this PDF: Steganography Instructions

— Dr. Paul Hand, Ph.D., Executive Director, Tapia Center