Soak It Up!* 04/11 Grade Level Setting Theme/Bottom Line Description BIAS: Stewardship Time Recommended Group Size FOSS Kit: State Standards:

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1 Soak It Up!* 04/11 Grade Level: 3rd grade Setting: River, field trip (off trail site if possible), or any site with soft surface trail and vegetation. Theme/Bottom Line: Add water to soil and you get some more than mud! Description: Students observe what happens when water is poured through different earth materials in a field setting. Then they compare the results to a classroom experiment. BIAS: Stewardship Time: minutes Recommended Group Size: FOSS Kit: Water State Standards: Construct, read and interpret displays of data including tables Ask questions and state hypothesis that can be addressed by the scientific method Explore the properties of water through experimentation Repeat science experiments to see if the same results occur, compare a model to what it represents Discuss the effects of people on the environment; identify erosion Materials list: 1. Large container of water that holds 1.25 cups of water per student 2. 1 paper cup with a hole in the bottom for half the students; Rulers for the other half of the students 3. Stop watches, for half the students 4. Colored sticks numbered 1 and 2; one set for every 2 students 5. Data sheets/booklets, pencils, clipboards, one for each student 6. Blue neckties(3-5) for the water droplets in the game Perc Through the Pores. Getting Ready: 1. Check with teacher to see if students have completed the FOSS kit 2. Pick up the box/kit of all the materials 3. Scout the site to make sure you have the topography needed for this activity. Nat Notes: This lesson builds on the Water FOSS kit that 3 rd graders in Poudre School District do. Student s background knowledge will depend on if they have completed the kit or not. The FOSS kit includes experience with the concepts of surface tension, properties of hot and cold water, condensation, evaporation, pouring water through soil and gravel and using water to do work. During this lesson students will be observing what happens when they pour water through different earth materials in a field setting. (If they have done the kit). They will also compare their results to what happened in their classroom experiment. Description of FOSS lesson: Students pour equal amounts of water through equal masses of 2 earth materials, soil and gravel. They measure the amount of water that drains through the earth materials and compare the resulting masses of soil and gravel,

2 using a balance. The concept that some earth materials, like soils, absorb more water than other earth material and that water flows more easily through some earth material, like gravel, is introduced. Introduction: 1. Welcome, introduce yourself. Restate the invitation for the students to return to the Natural Area with their families. 2. Since today is all about water the students will be investigating water in nature. Ask them how they have been investigating water in the classroom. Ask them if any of these same concepts from their classroom experiments might apply here in our natural area? For example, does water flow through soil here? (Yes!) During this lesson students will be observing what happens when you pour water through different earth materials in a field setting and comparing it to what happened (or what will happen) in their classroom experiment Body: 1. In the class experiment two earth materials are used: soil and gravel. But are all soils equal? In other words have they ever tried to dig a hole in heavy clay when it is wet? Dry? How about in sand? How about in a riverbed? How about in a garden plot? By now everyone should be able to agree that all soils are not equal. So will all soils absorb water the same? 2. Put the students into partners, or ask the teacher to assign partners. While this is being done, hand out the colored sticks to each pair and ask the students to look around and find 2 places where they think water will be absorbed differently (for example the soil under a tree and in a meadow or on the trail versus a vegetated area). Give them boundaries (remind them to stay on trail if it s an on-trail site) establish a signal that means its time to return and give them about 5 minutes to explore. They should find and mark 2 places where they think water will be absorbed differently. They can leave one of their colored sticks on each spot they choose. 3. Call everyone back to the starting area and ask them to share what they found. 4. Ask students how they would test these various areas to see which absorb water and how water flows through. Students may propose that you repeat the procedure they did in the classroom by digging up soil and pouring water through it. Explain that since this is a natural area, and everything is protected here, including the soil, we don t want to do any experiment that is going to disturb the soil (ie digging). Propose that students compare the 2 different areas they found by pouring water on them and timing how long it takes to absorb. 5. Ask students what things in this experiment might change the results (ie where the water is poured, how high the water is from the soil, the amount of water that is poured, how fast the water is poured etc). These are called VARIABLES. In science we try to control the variables, so that everything is the same except the thing we are studying, in this case the absorption of the water. It s important to make sure that all the other factors are the same (amount of water, how high the water is from the soil etc) 6. Pass out worksheets and ask students fill in their name, question and hypothesis. Go over the data sheet and model the procedure. Pass out equipment and remind students of the boundaries and the call back signal.

3 7. Have the pairs return to their chosen sites to perform the experiment. They should each do one pour and take turns as pourer and recorder. 8. Walk around and help groups as needed. If students finish early, have them try another spot for a third result. 9. Call students back with your signal. Ask them to share their results, following the data sheet. Highlight that water soaked into the vegetation faster than into the trail or bare soil areas. Ask students why (the roots of the plants create pathways for water through the soil). The absorption rate may also have to do with what type of soil (there is more air space in soil with large particles). 10. (If there is time) Demonstrate why the water flowed more easily through some materials, than others, by playing Perc Through The Pores. Perc Through The Pores: In an area where kids can spread out, explain that students are going to become soil particles. They will simulate different soil particle sizes and pore spaces between the particles. Designate 3-5 students as water droplets. The rest of the students will be soil particles. They will use their arms to represent three particles (sand- arms outstretched from shoulder (hands touching), silt- hands on hips, bent at elbow (elbows touching)and clay- arms down at their sides (shoulders touching). First model sand- students stand arm distance apart and ask water droplets to find a way through (they can duck down and easily move through the sand. ) Repeat with silt and clay. Ask students which was easiest for the water to move through and why. Explain the idea of pore space the space between soil particles that allows water to flow through. 11. Discuss how Perc Through the Pores relates to the experiment the students just completed. Based on their results, what kind of soil do the students think they used in their experiment? Why is there less pore space in the soil on the trail? (its compacted by people walking and there are not roots to create spaces in the soil) What if people walked everywhere in a natural area and not just on the trail? (the whole area would be compacted and all the vegetation would be crushed, so that is why we concentrate use on one small trail instead of the whole site). Explain to students that this is one reason that we ask people to stay on the trail. Additionally, this is a reason to walk through the mud (instead of around it) when hiking. As people walk around muddy spots, it widens the trail and makes a larger muddy area, so its better to get muddy and keep the trail narrow!

4 Conclusion: 1. Ask the students to sum up what they have learned in one sentence. Take a few examples. 2. Ask the students to explain why water doesn t soak into the soil at the same speed everywhere? Have them pretend that you are their mom and they are teaching you what they learned today. 3. Next time it rains challenge them to look around their school or home to see how the water is being absorbed into the soil. 4. Ask how today s activity explains why staying on the trail is good for nature? This lesson was written by Dolores Daniels, Susan Schafer, and Zoe Whyman. Perc through the Pores is a Project Food Land and People Activity

5 Name Question: Which place, or will soak up water the fastest? Hypothesis: I think will soak up water faster because Data: Pour #1 Pour #2 Where (describe the location where you are pouring the water) Height of pour, in cm Amount of water poured, in cups Speed (how long it took to pour the water onto the soil) in seconds How long did it take for water to soak into the soil (disappear from the surface) in seconds? What happened? Did it Splash Puddle Run off Soak in Bead up Erode (pick up soil and move it)? Describe the results. Discussion- Which pour soaked up fastest? What does that tell us about the soil in that location? Conclusion: Was your hypothesis correct? Why or why not?