Sara Rutzky

Wake Technical Community College

Introductory physical geology course primarily filled with non-majors

The activity is most effective if students have been introduced to streams and stream terms previously in lecture, but the activity is just as effective as an introduction to streams. There are some calculations, so an ability to solve an equation, do conversions, and perform basic algebra is necessary.

I do this activity with students in lab while we are talking about surface water in lecture. It can be helpful because it gives students a visual aid and hands-on aid for all sorts of water-related concepts.

Students will observe how a stream forms in a stream table and discuss how water and sand interact. They will observe erosion and deposition in action, as well as the creation of meanders, a delta, and other stream features like sandbars and cutbanks. Students will take their own measurement, and use these measurements to calculate parameters for the stream, such as velocity, gradient, and sinuosity. They will discuss the relative strengths and weaknesses of different measurement strategies. Students will use math in its scientific context, and start to see the relevance of math within science.

Students will work effectively in groups to create a stream, and will play with water and sand but keep the lab room clean. Students will also work together to solve algebra-level stream-related math problems and conversions.

Students work in groups around home-made stream tables. Each person in the group is assigned a role that is involved in maintaining the stream table (such as the hose-holder, the bucket-holder, the person who turns on and off the water, and the recorder). As a group, they turn on the water and observe what happens when water and sand interact on a slope. Once a stream has formed, they draw the stream, noting locations where erosion and deposition have occurred. Then, they take measurements of the stream channel and stream flow in order to calculate velocity, sinuosity, gradient, and discharge. This activity encourages students to work in groups, use math within a scientific context, and learn about how streams work in a hands-on manner.

During the lab activity, students answer questions in the lab, and work the math problems on their sheets. Once they are done, the students turn in the labs and I grade them. Points are taken off for misuse of or lack of units, and are given for a demonstrated understanding of stream processes.