http://www.readwritethink.org/files/resources/interactives/construct/
Some kids learn to read better through a “back door”. One of the back doors is “encoding”. These children learn the mechanics of word attack better by constructing words, rather than analysis of words. Construct-a-Word does a good job at this. Learners choose a word-ending cluster (word family), then drag initial consonants or blends in front to form words. The program tells you how many there are, and offers a “Print” option at the end.