See an excerpt from this phenomenal title from the award-winning Tell Me Why series, based on the books by Arkady Leokum.
What is erosion? How many different kinds of rocks are there? What is coal? What is an alloy? What is chalk? What are birthstones? All these and other important questions are answered in this DVD from TMW Media.
To order this and hundreds of other terrific, award-winning educational titles, go to tmwmedia.com