**Summary:** Students explore water temperatures from the surface to the bottom of Lake Erie, graphing and discussing the results.

**You Need:**

- 50 minutes
- Graph paper
- Pencils
- Ruler
- Downloads:

## Procedure

Create groups of six students and assign a station to each student in each group.

- The six stations are 1047, e10, 968, E42, 1003 and 1190.

### Part 1 – As a class

- Determine the minimum and maximum depth for all of the stations.
- Determine a scale for graphs (minimum and maximum depths and temperatures necessary to fit all data onto the graphs).
- X-axis – 0 to 25 degrees Celsius
- Y-axis – 0 to 35 meters

- Discuss reasons for setting ‘0’ at the top of the y-axis.
- 0 is the surface, the deepest station is 33 meters deep

### Part 2 – Each student

Using graph paper:

- Create a graph using the agreed upon scale
- X-axis – 0 to 25 degrees C
- Y-axis – 0 to 35 meters

- Label x-axis and y-axis
- Create a title including the station ID number
- Label the bottom of the lake at each station
- For example, station E42 is only 22 meters deep

- Plot temperature (degrees C) by depth (meters)

### Part 3 – In small groups

- Answer data sheet questions
- Have students compare their graph and data sheet answers with other students in their group.