You control a boat in the Grand Canyon and your goal is to reach the end of the river before the timer runs out. Every 30 seconds you will be asked an erosion related question and you get extra points if you get the answer right. You also get points for collecting gemstones and you must avoid logs in the river so you don't lose points. There are 20 questions in total during the game, all taken from subject matter that is required for teachers to cover in school. Works great as a review game when students have completed the erosion module in class.