1. Begin by reviewing the Plane in the Sky lesson and refresh their minds as to how they thought they might go about verifying that their map was accurate. Hand out a color photocopy of the map they created during that lesson. It will be important to photocopy their map because overhead markers wash away when wet or rubbed. (If you don not have access to a color copier you can scan the image onto a disk and print with a color printer, or let them use the original copy). The students will need a copy of their mapduring this lesson.
2. Ask the students how they can verify that their map is accurate. Many of the maps the students create will be different (which is okay). It is now time to get a more accurate version of the schoolyard, one that reflects what is on the schoolyard today. Point out the date of the aerial photograph and mention how things might have changed. An example of this may range from a large tree that may have died and been cut down to a new wing added to the building. It will be important for the students to examine what is on their schoolyard in detail. Ask the students how they think this should be done. Hopefully someone will say that the only way to make sure of their map is to go out and check!
3. Tell the students that like many scientists they will be assessing the accuracy of their map. It is important for them to realize that what is actually on the landscape may be different than what is on their map. It is important that what they have on their map doesn’t influence what they see in the investigation of the schoolyard. The students will need to have an open mind when they field check and do so in a way that allows accuracy. Places to examine closely in this investigation include places on the photo that appeared fuzzy or unclear, a place that they know has changed over time, places where group members think there are different things, places that might have shadows, etc.
4. Take the quadrant grid transparency and overlay it onto the maps that the students created. Divide the quadrants up so that each group has approximately the same number of quadrants and give each quadrant a number. Ask those groups to closely examine the areas they are assigned to try and identify questions they might have.
5. Give students the student chart handout. Ask them to write the numbers of each assigned quadrant and put that number in a corresponding box on the chart. A venn diagram can be used as an alternative activity.  See student handouts for details.
6. In the next box have the students write down a description of what they think is in that spot using only the aerial photo.
7. Field check the schoolyard. Have the students go to each of the quadrants assigned and describe what is there in the final box of the chart. Have them note if the information they gathered from the aerial photo is correct or incorrect or if the cover has changed since the aerial photo was taken. The main goal of this activity is to get accurate information.

Notes for 1st-2nd graders: This lesson is designed to check the maps they created for detail. If this age group does this activity at all they might do it as an entire class with supervision from the teacher.

Closure: Wrap up by allowing the students to meet as a whole group and discuss what they found. How accurate were their maps the first time around? What things did they notice about the field check that they didn’t notice on the aerial photo? Did they find anything on the schoolyard that surprised them? Explain that the next steps are going to update their personal maps and prepare a large classroom map with everyone’s input.

Homework: Using a copy of the grid, have the students draw a detailed version of the quadrants they studied. This will help them make the class map in the next lesson. Students should be ready to participate in a discussion and explain what is on their map in the nest class period.