New York’s Urban Ecosystem Lessons
This is the first in a series of four lessons on the permeability of surfaces in a watershed. These lessons can be done together or individually. If you plan on doing all the lessons in the permeability series, then you should consider doing them in the order suggested: Part 1, 2, 3, and then 4. This series works particularly well after the Watersheds series of lessons. In this lesson, students study satellite images of the location you have chosen, and draw inferences about the types of surfaces to be found in that location.
Materials and Resources
SuppliesA way for everyone to look at the same online Google Map at the same time. Google Earth generally has better images, but for this purpose you can also just look at the Satellite view on Google Maps. Projecting works best. This is also possible if everyone has their own screen and you provide very detailed instructions about what to look at when. A good color printer/copier might also be able to produce the satellite images you need, for distribution.
Before you get started
Tips for Teachers
Decide ahead of time what area you want students to model, and prepare the satellite images accordingly. It’s important that students share some familiarity with this location, whether it’s the location of your Oyster Restoration Station, the neighborhood of the school, or some other place that is accessible and part of your students’ daily lives. Since you’ll be visiting the ORS with your class anyway, the ORS could be an excellent choice. This series of Permeability lessons make more sense following the Watersheds lessons in the same unit. During the discussion, be sure to ask the students to cite specific evidence from the satellite images and/or their personal knowledge of the area, and/or encourage them to demand evidence from one another! Do your best to keep track of your students’ questions and predictions, at least in your own notes. As soon as possible, post a version of those discussion notes in a place where students can also see them during the next several activities. Building models is time-consuming! If you are going to follow this series through to that stage, one way to make it very much worth the time is to arrange an opportunity for students to present their models to decision-making adults. For example, if your location includes the school grounds, could students present their model (and proposals, if you do that part), to the principal, building manager, and/or head custodian for the building?
Remind students that you are in the midst of the study of watersheds, and if you like, ask them to summarize their questions and insights so far about what happens to rain water after it hits the ground.
Show students a street map of the location you have chosen, preferably on a large screen for everyone to look at together. You can do this using Google Maps https://www.google.com/maps/
Ask what they know about this place.
Point out familiar landmarks to help them understand what they’re looking at.
- Tell your students that ultimately, you want them to be able to create a model of the surfaces around the location you have chosen. In order to do that, they need to know: what are the surfaces around that location, and how absorbent are the materials we have available for our model? You’ll spend some time on both questions, starting with the location.
Hand out the Surface Types Diagram Ask your students
Based on your personal knowledge of the location, which surface types have you seen in the location you have chosen? Where?
Try to estimate what percentage of the location is covered by some of the different surfaces on the handout.
Encourage constructive disagreement and debate, and channel it by introducing more data...
Look at satellite images (you can do this on Google Maps https://www.google.com/maps/) of the location you have chosen.
Ask your students to fill out an Observation/Inference chart based on the satellite image.
Under observations, ask your students to identify areas on the satellite image that look like different types of surfaces, and to describe what they can see in the image.
Under inferences, ask your students to predict how permeable or impermeable they think each surface is. You might postpone the use of that vocabulary until they are familiar with the concept, and for now, ask something more like:
Predict which surfaces could soak up rain the most, and on which surfaces the rainwater would immediately flow downhill toward another surface.
Lead a discussion based on the satellite image
During the discussion, be sure to ask the students to cite specific evidence from the satellite images and/or their personal knowledge of the area, and/or encourage them to demand evidence from one another!
Do your best to keep track of your students’ questions and predictions, at least in your own notes. As soon as possible, post a version of those discussion notes in a place where students can also see them during the next several activities
Ask questions like:
Where do you see evidence for permeable surfaces? Where do you see evidence for impermeable surfaces?
Again, you can postpone using the vocabulary (“permeable” “impermeable”) until students are very comfortable discussing the ideas behind the words. Then it’s great to introduce the words.
- How do you figure out some of that information from the satellite image? What areas seem most obvious, in terms of whether they are permeable or impermeable? What areas are most in doubt for you?
Continue the discussion by asking:
Do you want to revise your estimates of the percentages of different surface types?
- What new questions do you have about the types of surfaces in our area of interest?