This idea came from the Bakers and Astronaut Reggio-inspired blog. I started the children off with an AB pattern and encouraged them to continue it. It began left to right but the children gravitated to a vertical flow because it was easier for them to understand that yellow goes under blue and blue goes under yellow.
Once they understood that, the post it notes flew!
They filled the bottom half of the door:
Since they ran out of space on this door we moved to the other door and I offered the children their choice of colors:
Three colors was much more challenging, and they worked together to correct mistakes noticing when the pattern was off.
Hopefully they will get the concepts of patterns soon and I can stand back and let them design their own creations out of color and shape.