I am a volunteer at my local CoderDojo chapter, an organization that does software mentoring for kids 8-18. I try to get kids interested in computer science by teaching them to build fun Arduino projects that use color, motion and social project-based learning. We sit in a large room and when kids walk in the door I want them to be attracted by a colorful LED sign with lots of changing color patterns.
This project is also ideal for schools that have display cases that want to highlight the programming skills of students in classes or science clubs.
My design goal was to build an attractive sign you could build for under $20 in about an hour. My goal is to keep the design as simple as possible with a minimum of steps.
I use a plastic bin to carry my Arduino kits around. It is about 20 inches wide, so I decided to make my sign 19 inches wide. To keep the proportions of the word "ARDUINO" this implied that I need the sign to be about 5 inches high.
Since the word ARDUINO has 6 complex stroke letters and the simple letter "I", I calculated that each letter would need 7 or 8 LED pixels and the "I" would need only 4 pixels. I figured I could get by with a single 50 element LED string.
You can get these on e-bay for about $11 to $14 with shipping. Mine came in about a week.
Here are some of the search keywords you can use on e-Bay:
50PCS WS2811 RGB Full Color 12mm Pixels digital Addressable LED String
Here is a sample link on e-bay: