Students will need 2 science times if they test 2 different design solutions and/or want to modify the model they built.
See the reflection: From Two Designs to One. Instead of companies developing and modifying 2 designs, teams choose the best design or integrate the two design ideas to test and evaluate.
2-ESS2-1. Compare multiple solutions designed to slow or prevent wind or water from changing the shape of the land
Students build and test solutions to slow or prevent water erosion on a slope.
Science Practices - Appendix F
- Planning and Carrying Out Investigations (SP 3)
Students take observations to compare which erosion model best met the criteria goals.
Cross-cutting Concepts - Appendix G
- Systems and System Model (XC 4)
Students build a model to show run-off erosion and test ways to change the erosion system to slow or stop erosion to understand how people can apply these solutions in the real world.
erosion tables set up in a central out door location
prepare 6 containers for teams to use for their erosion model test ( I am using 1 gallon water bottles and cutting out one side)
set out materials to be used for the erosion model solutions (including other materials that teams may have requested from the previous lesson)
rocks popsicle sticks weed block fabric
cue company jobs on the projector
12 bags of soil; approximately 1/2 gallon per bag (I am using cactus and palm tree soil since it has organic matter and sand; less absorbent)
Students tested one erosion design in this time frame. The second bag of soil is for the 2nd design, since the first set of soil will be soaked from testing. I discuss variables and how the wet soil changes the variables when testing the erosion model.
6 containers to capture 'run-off'
(6) 12 oz drinking water bottles (for water)
(1) 5 gallon bucket with water for students to fill bottles
6 tubs to hold team materials
copy team jobs and observation forms 2/team - one is for the 'contract'; cut apart the second copy and staple job descriptions with the lab papers that go with that job. (See list "Each Team Will Have")
6 vinyl tablecloths
When taking erosion model apart:
1 bucket to rinse materials
2 buckets for soil
1 bucket for rocks
1 bucket for gravel
Each Team Will Have:
2 bags of soil - May want to start with one bag of soil / team and use the second one for the next science lab.
1 'hillside' container for erosion model (gallon water bottle with side cut out)
small rocks as the bottom layer in their erosion model - students and I discuss that this is the bedrock that is under the soil layer
(1) 12 oz water bottle - used to pour water down the slope
1 container to capture run-off
geologist and hydrologist observations forms - staple job description to the front for geologist and hyrdrologist observation form
2 -3 copies of the erosion solution diagrams - staple "Lead Engineer" job description" to the front
original diagram, materials, procedure - staple "Project Leader" job description to the front
Science starts with a question, usually written on the board. This allows students to time to consider today's topic before the lesson has officially begun. I have established this routine with the kiddos to keep transition time short and effective.
Question of the Day - How will your company know how well your model slowed or stopped erosion?
I am referring to the criteria that was established in the last lesson, to keep teams focused on the goals of their lab, optimizing the most time for the lab.
Since I am asking students to recall specific information, I call on volunteers to answer the question.
"Right your criteria for your erosion models is first to have clear water run-off and then see if you can slow or stop water run off.
The criteria is posted on the board.
"Last week you drew up plans for erosion solution models. Today you will build and test and write observations on how your erosion solution models."
"After I return your company's' erosion solution plans, please move to your team table."
Now the companies have their diagrams, procedures and material list. Next they will identify the jobs they will do.
"Companies, today you will use your selected erosion solution diagram to build and test your solutions! Please take a couple of minutes to discuss your erosion solution diagram, material, and procedures with your company."
It has been a couple of days since the students designed their solutions, I want them to take a couple of minutes to review their plans.
I walk around the room to answer questions and to check that companies understand their erosion solution plan. Then I signal their attention.
"To help your company build and test your erosion solutions, each person in your company will sign up for specific jobs. I will explain the jobs and then you will have 5 - 10 minutes to decide who will do which job."
I use the smartboard, to show and explain one job at a time:
Project Leader - shows the design to be tested and reads the procedure and material list to the company; redirects focus of the company when needed and helps other company members
Lead Engineer - checks that the model matches the diagram before testing; after testing, writes observations on the diagram about what worked and/or did not work, and what would be the next steps with the model; company members help with observations
Geologist - writes observations on how the hill changed after each test; describes the soil; company members help with observations
Hydrologist - pours the water down the hill (company members can take turns with this task); writes observations how water moved on the hill and how the water looks in container, include observations about how water flowed, fast, slowly.
"Companies, remember to allow everyone a chance to say which job they would like and know that there may need to be compromises."
"Just like you switched tasks when you studied wind, wave and water erosion, you may choose to switch jobs for each test."
I hold up the 'contract' for task assignments, "I will pass out your contracts and the hydrology and geology observation forms, while you discuss jobs. After all the forms have been passed out, I will start the 5 min. timer. When the timer ends, all teams will stop discussions so I can give the next set of directions."
The 'company contract' lets me and the team know who is accountable for each task.
After I pass out the last form, I start the timer for 5 minutes.
I want to keep the time short so students do not use a lot of lab time deciding who will do what, or hold up other teams that are ready to go. If some teams have not chosen tasks yet, they will complete this task after I give the next set of directions.
When the timer sounds, I signal for students attention.
I project (see p.8) a summarized version of the directions below.
"The last time you worked with your company you decided which design you would build first. This is the first erosion solution your company will build and test. After the hydrologist, project engineer, and geologist having taken the observations, then the company can test the 2nd design and take observations."
Companies when you write your observations, remember to write which design you are testing and if it is the first or second test for that design.
I hold up the following as I explain what the tub that I will pass out momentarily:
"Each team will get a slope container, container to catch water, the catch basin, rocks for the bed rock, 2 bags of dirt, one for each design, 1 water bottle to fill with water and a baggie to pick up the materials listed on your companies material list."
"After the Project Leader reads the material list and procedure to build the model and the company agrees that nothing needs to be changed with the list or diagram, then the material for the model building can be picked up. Use the baggie in your bin to gather and carry the material back to your company table.
"If the company sees that other materials are needed, this will need to be added to the diagram, labeled and then these materials may picked up from the table."
"Geologists will place the bed rock in the bottom of the slope container. Companies will build your model at your assigned area, and then when ready, the project leaders will take the model and set it up on the erosion table slot that shows your company name."
I chose to designate which erosion slot they would use so that I could quickly monitor the teams' progress.
"When a team is ready to test, the hydrologists will pour one bottle at a time over the hill. The hydrologist will pour a total of 2 bottles. Each water bottle is a test. So test 1 happens after one bottle of water is poured and test 2 is for the 2nd bottle of water that is poured.
The geologist, project engineer and hydrologist will write the observations. Project leader, you will help remind the members about their jobs and help with observations."
"After ALL observations for test one and two have been taken, and there is time, your company may choose to modify your erosion solution design and test again."
"Alright, lets get started! Project leaders, look for the bin that has your company name."
Materials were set out before class on the back table so that students could easily pick up their materials.
I move to each group to observe group dynamics and to check that they are doing the work of scientists, writing observations and modifying diagrams when needed. I ask each team to explain how their erosion solution model works.
I ask questions about why they chose to change part of their model. Is there a way to slow the water flow? What would happen if the water continued to flow down the hill without any plans to stop the erosion? What do you think would happen if the hill was sandier? What could you use as a model for plants to test how much erosion happened when there were trees? What would you want to try next? How is the model like a hill how is it not?
"Welcome back companies. I saw some interesting solutions. You will have another opportunity to test another design the next time we meet for science."
"Afterwards you will decide which erosion model to share with at the Rock Away Town Council and prepare your presentation."
I mention this so students know what to expect for the next couple of science classess.
"Before we clean up, I would like each company to share something about their lab today. You could tell us something you learned, what you would do differently next time, what you liked or did not like about the lab."
I have sentence starters (see p. 7) projected on the board to help students frame their answers.
"The project leader will be your spokesperson. Your company has 2 minutes to decide what it will share."
After teams share, I tell them what I saw that went well and congratulate them for all their hard work. Noting how they did the work of engineers, testing and evaluating.
I hold up one of the diagrams and point out how they remembered to use a different colored pen to write their observations about how the model worked.
I project and review the directions for clean up (see p. 6).
I direct teams to place their lab papers on the back table. I will review the observations and diagram notes to get an idea what the students are experiencing and learning and to write back to the company.