The Physics Teacher
Putting large numbers into human perspective by using ratios of a known quantity to an unknown quantity is an important scientific skill. An astronomy activity that encourages the use of estimation and helps students get a handle on large numbers is the making of a scale model of Earth and Sun that is relative in both size and distance.
Moldwin, Mark, "How Big Is Our Sun?" (2000). Aerospace, Physics, and Space Science Faculty Publications. 17.