I started teaching the concept of the mol (not the animal...the amount) in chemistry this week. The problem is, the mol is such an impossibly large number to comprehend (6.02 x 10^23, or 602 sextillion, or 602 followed by 21 zeros) students often don't grasp the quantity of things we are attempting to count. So, I had them do a quick project on quantifying the number of things...anything...in a mol. They had to relate one mol of an object to a concrete idea for people to visualize. Many students just looked at the length of an object like a pen or a keyboard key. Some others measured area, and still others measured volume.
For the project, they gave an example of a dozen, a gross (a dozen dozens), one million and one billion. I got some great projects from this...better than I anticipated when I assigned it. Below are some of the projects I had students turn in for the assignment.