Thanks for sharing this great technique Michael. The use of simple analogies to help build a learning foundation is a great skill that not all instructors use. Students need concepts they can understand and relate to more complex concepts. By providing them mental images to compare with the more complex concepts the are better able to make the connection and understand the more complex concept. This skill is used a great deal in the K-12 environment but is incredibly useful in higher education well. I have also seen some very creative exercises done with simple and everyday items like building blocks and puzzles. A puzzle with 1000 pieces uses the same process as a puzzle with 4 pieces, it just takes longer to constantly repeat the process to find the correct location for all 1000 pieces. One is not harder than the other but one may take more time. Regards, James Jackson