Weather is a challenge for all gardeners, but urban landscapes have unique climate issues caused by man's manipulation of the land, including including the phenomena of heat islands and excessive runoff during rainstorms. In this lesson, students will investigate urban temperature and rain patterns.

Standards (Microsoft Word document)

Materials:

• thermometers
• rain gauges (You can purchase gauges or make your own using directions at Making Weather Tracking Tools)
• notebooks for use as weather journals
• cake pans (old ones or new foil ones)
• potting soil
• grass seed

To investigate temperature patterns:

1. Take students to your schoolyard and choose a variety of areas to investigate (near buildings, in full sun, in shade, near streets, in areas with vegetation, and in areas without vegetation). Use a thermometer to take data for a temperature journal. In the journal, carefully label and describe each site, and take readings at each one over the course of several days.

2. When you return to the classroom, summarize your results on a chart. To stimulate discussion, ask students, Did you find any differences? Why do you think you found these differences? How did the temperatures compare on different days?

Next, investigate water runoff patterns:

1. Before a rainstorm, have students place rain gauges in various sites around your schoolyard (open areas, under vegetation, near buildings without gutters, and near buildings with gutters). After the storm, have individuals or teams record measurements in weather journals. Also give students time after the storm to make observations of water patterns on the ground (areas of standing water, signs of what happened to the rain when it fell, and where it went. Back in the classroom, discuss what their data and observations might data mean. Ask students, Did each of the gauges catch the same amount of water? What does this say about the impact of rain on different locations in our schoolyard? Did you find evidence that stormwater might have an impact our school garden?

Making Connections

Model rainwater patterns in the classroom to help demonstrate your findings:

1. Fill two old cake pans with soil. In one pan, plant grass seed and let the seed grow for about a week to establish some roots. Leave the second pan unplanted.

2. Tilt both pans and simulate rain onto the soil using a watering can. What happens? (The soil in the pan without plants will erode, but the soil in the pan with roots should stay in place.) Ask students to think about the implications of stormwater erosion in the schoolyard.

3. You can modify the experiment by creating a third pan with mulch covering the soil and a fourth pan filled with plaster to simulate concrete. Compare each surfacing and make conclusions about the impact of different types of surfaces on your environment.

• Invite a local meteorologist to talk to you class about local weather patterns.
  
• Research global climate change. Ask students to read articles that both support and refute this phenomenon and discuss how and why opinions vary.
  
• Research urban greening and its impact on the heat island effect
  
• Build a rain garden! The Low Impact Development Center provides some rain garden templates. Also check out our feature, Rain Gardens to the Rescue.