# Streams and Water Quality

Hydrogeologists and environmental scientists often study streams and lakes to determine the quality of the water. Water quality depends on several factors including sediment load and pH (level of acidity). Water quality in these environments is important, because this is where many people get their drinking water. In this activity, students will measure stream velocity, sediment load, and pH.

Safety
Make sure students aren’t too close to the water, so they won’t fall in. Take special care after a rainfall, when the banks can be muddy and slippery, and the water may be moving more quickly than normal. Be aware of weather and flash flood warnings. Make sure that your stick or other floating object is handled with care so as not to cause injury from a sharp point or edge. Bring a first aid kit.

Materials

• Stopwatch
• Measuring tape/meter stick
• A stick or other floating object that can be discarded after experiment
• pH paper and corresponding color chart
• Paper and pencil
• Calculator

For the Teacher
Prior to conducting this activity, particularly step 6, the teacher should determine the cross-sectional area of the stream. Measure the stream’s width with a measuring tape, and find average depth with a meter stick. Cross-Sectional Area = Average Depth x Width.

Procedure

1. Travel to a local stream, preferably a place where it is easy to stand on the bank. With the measuring tape or meter stick, measure out 2 meters parallel to the stream.

2. Have a student stand at one end of the measuring tape upstream (Point A) and another student stand at the other end downstream (Point B). Hand the student at Point B a stopwatch.

3. Hand a third student a stick or floating object that is large enough to be easily seen.

4. To measure the velocity of the stream, the student with the stick drops it in the stream about 2 feet beyond where the student at Point A is standing. When the front end of the stick reaches the measuring tape at Point A, then that student says “Go,” and the student at Point B starts timing. When the front end of the stick reaches the end of the measuring tape at Point B, the student at Point B stops timing. Record the time on the stopwatch.

5. To calculate the velocity, the equation is Velocity = Distance/Time. So in this case, Velocity = 2 meters/X seconds, where X is the time on the stopwatch. (For example, if the time on your stopwatch is 2 seconds, then the Velocity = 2 meters/2 seconds, or 1 meter per second.)

6. After finding the velocity of the stream, calculate discharge, the amount of water flowing past a certain point per second. An important indicator of what organisms live in the stream, discharge also influences a stream’s ability to dilute chemical pollutants. To determine discharge, use your measurement for the stream’s cross-sectional area, which is expressed in meters squared, as indicated above. So the equation for discharge (Q) is Q = Cross-sectional area (A) x Velocity (V). (For example, if A is 10m ² and V is 1m/s, then Q is 10m ³ /s or 10 cubic meters per second.)

7. If there is time left, find the pH of the stream using pH paper and a color chart. Simply take a piece of pH paper, dip the end of it into the stream for a few seconds and pull it out to see if there is a color change. Then use the pH paper color chart key to determine how acidic or basic the water is.

8. Discuss how the velocity, discharge, and pH of the stream might affect the biology of the stream and the quality of the water as a source of drinking water for humans. Why is the stream acidic? Why not? Could there be human or animal contamination? Does the stream’s velocity affect which animals you see in the stream? Are there fish or insects? How many and how big? Discuss the biodiversity of the stream. Are there many different types of organisms or a lot of the same kind of organism?

# Be a Paleontologist!

A paleontologist is like a private investigator, searching for clues and evidence of past life. These clues, preserved in sediments or rocks, are called fossils. In this activity, students are asked to think like private investigators working on a case: Where is paleontological evidence of past life likely to be discovered?

Safety
Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. If near a stream, take care: Do not get too close to the water, and be aware of flash flood warnings and fast-moving water. Watch the weather, and check for ticks after returning to the classroom.

Materials

• None

Procedure

1. Take a short walk outside and consider the landscape. If you were a paleontologist, in which of the environments nearby would you expect an animal or plant fossil to be preserved?

2. Think about how fossils are preserved. Are they preserved in places where sediments are deposited or where sediments are eroded? Would a fossil be preserved on a basketball court? Why or why not? Would a fossil be preserved in a muddy area near a stream or lake? Why or why not?

3. What types of rocks would have fossils in them? Would igneous and metamorphic rocks contain fossils? Would sedimentary rocks? Why?

Geologists, cartographers (map makers), and surveyors use compasses to make maps and determine where they are. Hikers use compasses to find their bearing in the wilderness in hopes that they won’t get lost. Sailors used to use compasses to find their way across the ocean and explore new territories.

Many people now often use a Global Positioning System (GPS), but it is important to know how to use a compass because there are still many applications of compasses — and not everyone can afford a GPS. Mapping is also a very important tool for Earth scientists. Maps can show everything from roads and buildings to the rock layers beneath the surface of the Earth. In this exercise, students will make a map of the school’s campus.

Safety
Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. Taking a first aid kit is a good idea. No flip-flops should be worn outside. Be aware of the weather, and check for ticks after returning to the classroom.

Materials

• Compass or several compasses (Nothing too fancy, just a simple plastic compass will do. However, it’s best to have a compass with azimuth readings instead of quadrants. An azimuth compass goes from 0 to 360 degrees. A quadrant compass has four quadrants of 0-90 degrees each.)
• A handout with predetermined bearings, a starting point, and paces between 4-6 bearings for each student (see BearingSamples.pdf)
• A site marker or prize for the end of the exercise
• Sheets of standard 8.5”x 11” white paper for each student
• Pencils

For the Teacher
Prior to conducting the activity, the teacher should create a handout of predetermined bearings and paces between bearings. Give a copy of the handout to each student, along with a pencil and a plain sheet of 8.5”x 11” white paper. Show students how to use a compass to get bearings. A bearing is simply a direction in degrees on a compass. For example, 0 degrees is due north, 180 degrees is due south, 90 degrees is due east, and 270 degrees is due west. Any bearing between 0 and 90 degrees is a northeasterly direction, and so on. Ask for volunteers to use the compasses.

Procedure

1. Use your compass to determine the direction you must walk the number of paces specified on the handout. For example, if the first bearing from a designated starting point is 75 degrees and 25 paces, hold the compass at eye level and turn in place until the north arrow is pointing to 75 degrees. Then walk in a straight line for 25 paces along that bearing. Continue to the next step.

2. After you complete the exercise and reach your final destination, draw a map of the school campus. Create the map in such detail that a new student would be able to easily find his or her way around. Items to include are buildings, trees, tables, blacktops, playing fields, and surrounding roads. Also important maps components are scale, legend, a north arrow, and the title of the map.

3. Use your compass skills to make your map more accurate in scale and more realistic. For example, you can turn paces into actual measurements. Maybe your pace is 0.3 meters, or about 1 foot. If you walk 102 paces along a wall of the school holding your compass at a bearing of 90 degrees, you could determine that 102 paces x 0.3 meters = 30.6 meters. Therefore, your map must include a line representing a wall that is 30.6 meters long, or about 100 feet, running from east to west (because the bearing is 90 degrees).

# Building Geology: Rock and Mineral Hunt

Observation is a vital part of the scientific process, especially in Earth science. Before Earth scientists make hypotheses and theories, they observe the rocks around them for answers to questions, such as: What rock types are present? How old might they be? What do fossils and rocks tell me about the depositional environment? Was there active volcanism or faulting in this area? Students will use their observational skills to examine rocks they find on the exterior of the school building and on the ground on the campus.

Safety
Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. Taking a first aid kit is a good idea. No flip-flops should be worn outside. Be aware of the weather, and check for ticks after returning to the classroom. Washing hands after this activity is recommended to remove unwanted minerals such as lead.

Materials

• Geologic map of the collection area

Procedure

1. Take five minutes to find examples of sedimentary, igneous, and metamorphic rocks in the area around the school.

2. Discuss the rocks that your class collected and the minerals in the rocks. Can you identify any common minerals, such as quartz or feldspar?

3. Examine the geologic map of the area and discuss why you found these particular rocks and why you didn’t find other types of rocks.

4. Now walk around the school and examine the materials used to make the building. Discuss: Is the school made of brick, limestone, granite, or some other material? Do you see igneous, metamorphic, or sedimentary rock? Is the building composed of human-made material? Where do the building’s rocks come from? Are they found in a local quarry, or are they imported from far away? Do other buildings nearby have similar rocks? Are there fossils in the rocks? If so, what kind?

# The Human Rock Cycle

Students, like adults, have various learning styles. Some of us learn best by talking and listening, others by reading. Many of us, including young students, learn best by doing — by moving, exploring, touching, and feeling. Acting out geologic processes can be a powerful way of building understanding.

Safety
Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. Taking a first aid kit is a good idea. No flip-flops should be worn outside. Be aware of the weather, and check for ticks after returning to the classroom. Also, no rough play.

Materials

• None

For the Teacher
Prior to conducting the activity, the teacher should divide students into groups of about three or four. Assign each group, in secret, a rock type — igneous, sedimentary, or metamorphic — and tell them to discuss privately their strategy for acting out the group’s assigned rock type. No talking with members of other groups!

Procedure

1. Quietly discuss with members of your group some creative ways to act out the rock cycle. How is your rock type formed? How does it age? How is it used by people? What does this look like?

2. One group at a time, make your dramatic presentation. You can make noises if appropriate, but no talking!

3. Once each group’s presentation is over, allow observers to guess which rock type was being acted out. What evidence suggests one rock type rather than another?

4. After all groups have presented, discuss the rock cycle. How do the rock types differ? What do the processes that create them tell you about their age, location, composition, potential uses, and other characteristics?

# Writing Earth Science

Earth science is more than measurements, maps, charts, and graphs. The language of geoscience, full of unique poetry, offers another avenue to understanding. Offer students a chance to flex their writing muscles in the context of Earth science.

Safety
Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. Be aware of the weather, and check for ticks after returning to the classroom.

Materials

• Lined paper, preferably in a hardback notebook
• Pen or pencil

Procedure

1. Find a comfortable spot outdoors, whether far from school or right outside your classroom, and observe the natural world. Can you see earth — and is there anything living in it? Can you hear moving water? Can you feel a dry breeze?

2. Write a poem describing the natural world where you are. Include as many sensory details as possible. What can you see in the sky, feel in the ground, smell on the earth, taste in the air, hear all around?

3. Connect these observations with what you’ve learned about Earth science in the classroom. What is the history of this landscape? How did these landforms and organisms come to be? Where and when will the story of these natural materials, forces, and processes continue?

4. If time permits, use your first draft as a starting point for further investigation and research. Maybe study the local geology or search the Web for information on the history of industry in the area. Write a second draft, adding depth to your first impressions with these new understandings.

# Earth Science Art

Half the fun of Earth science is experiencing the aesthetic beauty of the natural world. Our appreciation of nature can be enhanced by understanding the geoscience that underpins natural systems and processes. In this activity, students are invited to integrate scientific understanding with artistic expression.

Safety
Keep art materials away from your eyes and mouth. Wear sunscreen if outside for an extended period. Wear sunglasses on a sunny day. Be aware of the weather, and check for ticks after returning to the classroom.

Materials

• Selected art materials, such as sculpting clay, colored pencils or pens, paints and paintbrushes, paper, etc.

Procedure

1. Find a place outdoors to work. Collect your art materials, and pick a subject for your artwork. Which part of the scenery will you work on?

2. Before beginning your picture or sculpture, talk about what you see and what you plan to create. Why did you pick that part of the outdoors? Does it look exciting or interesting?

3. Talk about what you’ve learned in Earth science about what is around you outside. Why does the look like it does? Is it flat or hilly, bare or green with plants, worn away by water or ruffled by wind?

4. Maybe you’ve chosen to focus on a rocky outcrop, a stand of trees, or an area with lots of birds. How does what you know about Earth science help you understand what you see? Do you see rock layers you might not have noticed before? What kinds of trees and birds do you see?

5. Draw, paint, sculpt — create! Practice your observation skills by putting lots of details into your artwork so that another geoscientist who has never seen this area before would be able to find and recognize it using only your art as a guide. When you’re finished, hang your art in the school for others to see!

# Look Up! Observing Weather

Adapted with permission from The Weather Channel and the National Oceanographic and Atmospheric Administration (NOAA).

Weather is a very important part of everyday life. Every morning we look at the weather report to decide on what clothes to wear and how early we should leave for school or work. To get a better idea of how meteorologists (scientists who study weather) make weather predictions, students will begin their own weather journals and make rain gauges. Meteorologists use tools and techniques like these to understand climate, patterns of weather over large areas and long periods of time.

Safety
Glass jars may be used in place of plastic jars, but be careful that the glass jar is not over a hard surface. Only an adult should handle the hammer and nails. Wear sunscreen if outdoors for an extended period of time. Wear eye protection such as sunglasses when looking at the sky, and neverlook directly at the sun. If using a thermometer, only use an alcohol thermometer, never mercury. No flip-flops should be worn outside.

Materials

• Pencils
• Notebook with lined paper
• Straight-sided plastic container, with a diameter of about 2 inches or less (such as an olive or peanut butter jar).
• Coat hanger or wire bent to make a holding rack
• Measuring spoons: 1 tablespoon (which equals 3 teaspoons) and ¼ teaspoon
• Hammer and nails, or duct tape to secure the rack
• Felt-tip marker
• Container of at least a liter of water

Procedure

1. Working in groups and using the notebook, record observations about clouds, temperature, atmospheric moisture, wind, and precipitation. An example could be: Wispy clouds high in the sky (cirrus clouds). Temperature feels between 50 and 60 degrees Fahrenheit (or measure degrees Celsius). Atmospheric moisture is low and there is no current precipitation. Mostly sunny with wind from the NW at 5 miles per hour.

2. If desired, continue this weather journal for a week, a month, or a semester. At the end of the observations, note any weather patterns or irregularities. Perhaps there was a hurricane, or maybe it was unseasonably warm for that time of year. Try to explain these occurrences. What does the weather say about the climate?

3. Rain gauges are used to gather and measure how many inches of precipitation have fallen over a unit area during a set period of time. So the first task is to make a scale for the container that shows how many cubic inches of water are in the container. One cubic inch of water is about 3 1/4 teaspoons (the same as one tablespoon and ¼ teaspoon), so pour 1 tablespoon and ¼ teaspoon of water into the container. Then drawing a short line at the level of the water. Looking closely, the top of the water will seem to be slightly curved and thickened. Draw your line so that it matches the bottom of the curved surface (which is called a meniscus). This line corresponds to a rainfall of one inch.

4. Add another tablespoon and ¼ teaspoon of water to the container and draw another line. The second line corresponds to a rainfall of 2 inches.

5. Repeat step 4 until there are at least five marks on the container. This will be enough for most rain events, but adding another line or two is a safe bet.

6. Find a location to hang the rain gauge where there is nothing overhead (such as trees or a building roof) that could direct water into or away from the gauge. The edge of a fence far from buildings is often a good spot. Another possibility is to attach your rain gauge to a broomstick driven into the ground in an open area. Be sure to record rainfall soon after a rain event to avoid false readings caused by evaporation.

7. Get outside and empty the gauge after each reading. Discuss: How much time must pass before you observe a pattern? What do you think are some other ways scientists directly study weather to understand climate?