Word Power Tower

I found the idea for Word Power Tower online http://pinterest.com/pin/170925748327147023/.  My students have mastered the words so I need to add first grade sight words to new cups. Now they have started creating differents shapes & designs instead of simply stacking them into a tower. Here is a heart. :) We also use the power tower to practice addition facts. They are doing awesome with this as well. Just a pringles can & some contstruction paper taped on. It is hard to believe but this is one of the most chosen Daily 5 activities.