Lesson Plan Template: Guided or Open Inquiry
Learning Objectives: What will students know and be able to do as a result of this lesson?
Students will understand the issues of water pollution and the importance of access to clean water. Students will experiment with filtering various substances from water by making their own simple water filters. Observe and draw conclusions based on their experiment.
Students will design, construct, test and evaluate a water filter that will be used to produce potable water.
(This lesson is one part of a larger unit.)
Prior Knowledge: What prior knowledge should students have for this lesson?
Students should know that water is a limiting factor. Students should also know that safe drinking water is not available for all organisms. Students should also be aware of some sources of contamination of drinking water.
Guiding Questions: What are the guiding questions for this lesson?
Please see attached Materials List to prepare Dirty Water and materials for filter.
Dry erase boards are useful in class discussions. A dry erase board and marker for each table would be useful when asking guiding questions.
After showing the students the dirty water you prepared. Ask:
1. Would you drink this water?"
Most students would say no.
2. What are some contaminates in this water?
Students may mention soil, leaves, bacteria, fertilizers and pesticides.
3. What are some sources of these contaminants or water pollution?
Ask students to discuss in groups and write a list for their table. Then list the possible sources of water pollution on the board. Students may mention oil spills, bacteria and other organisms like pathogens, toxic chemicals from factories or household chemicals, litter, run-off from city streets that might include chemicals, industrial waste, human waste, agricultural waste from farms, etc.
4. Ask the students to identify which materials in the dirty water may be related to these contaminates.
Students may say the small particles are microbes or chemicals. Oil could have come from garages, parking lots, or service centers. The food dye could be fertilizers, or chemicals or drugs. The leaf litter could be from run-off, and trash from neighborhoods. The soil could represent other types of waste.
5. Is it possible to remove all contaminates from this water?
Students may mention ways to remove bacteria and microbes is by boiling the water to kill bacteria, microbes, parasites. Students may also mention trying to filter some of the larger particles. Address the misconcetion that boiling is the only way to kill microbes. Mention inventions such as solar powered water filters etc.
6. What steps do you think are necessary to make this water safe to drink?
Allow students to discuss with their groups and share their answers using a class discussion.
Some may suggest the particles need to be taken out, some may suggest removing the bacteria, and some may suggest removing the food dye. Some students are familiar with methods used in camping and may mention iodine tablets.
Take this opportunity to explain point-of-use water treatment systems and filed water disinfection techniques – these are often used by recreational enthusiasts, survivalists, military personnel, and others that must obtain drinking water from untreated sources. The purpose of these devices is to make unchlorinated water potable. Although these devices do remove some contaminates that they cannot make the water completely safe.Many of these devices are available for campers and hikers. Address the misconcetion that boiling is the only way to kill microbes. Mention inventions such as solar powered water filters etc.
Introduction: How will the teacher inform students of the intent of the lesson? How will students understand or develop an investigable question?
The teacher can introduce the lesson by discussing water as a natural resource and potential limiting factor for organisms. National Geographic has a short video clip about freshwater as a natural resource.
This video requires Flash.
Teacher will present the inquiry lesson to the students as role playing task. They are part of a team of engineers who have been hired to develop a filtration device to help the citizens of a country that does not have access to safe drinking water. Their team will focus on the filtration stage of the process. The filter they design must be composed of simple inexpensive materials.
Investigate: What will the teacher do to give students an opportunity to develop, try, revise, and implement their own methods to gather data?
The students will meet as a team and discuss the problem they need to solve.They should determine the materials they would like to use and how they would like to use them. They should draw their design and label the materials. The team should perform any preliminary tests with the materials before building. Their proposal should include a sketch of their filter.
Students will test their prototype. They should make detailed observations and agree on a way to record their results. Most students will take pictures or video for comparison. They should present their design to the class and explain their reasoning. Their classmates will offer feedback.
Some questions they should keep in mind:
1. Did another team's filter work produce clearer water than yours? What part of their design helped them to produce these results? How was it different to yours?
2. Which parts of your filter worked well? Which parts of your filter did not work well? How do you know?
3. How could you improve your filter? What materials would you need? Would you use materials in a different way or order?
The students will then make improvements on their design to increase the clarity of the water. They should test their revisions.
Analyze: How will the teacher help students determine a way to represent, analyze, and interpret the data they collect?
Their presentation can incorporate media, either pictures or video of their results to provide evidence of their observations.
Closure: What will the teacher do to bring the lesson to a close? How will the students make sense of the investigation?
Revisit your guiding questions, provide clarification if necessary. Students will answer the following questions and then discuss as a class revisions and results of those revisions.
1. Did your filter prototype succeed in making potable water for the citizens of the country?
2. What aspect of your design worked best? Why?
3. Would you drink the water that passed through your filter? Why or Why not?
4. If you could have used material or materials that were not provided to you, what would you have requested? Why?
5. What are some challenges of designing a filter for household use? What are some challenges to designing a filter for large scale use?
Evaluation of students grades should not be based on the clarity of the water, but should be based on how well the students demonstrate his/her learning from learning based on their written observations, improvements on their design, explanation of their choices in design, and their responses to questions at conclusion of the activity.
Teachers will begin this unit by ascertaining the level of prior knowledge students have about the source of their drinking water. Allow students to share ideas and discuss. Record any concepts they may have already mastered (gifted students) or any concepts for which they will require scaffolding (standard students, or level 1 and 2). Do not correct any misconceptions at this point.
Consider contacting your local water treatment plant or contact the local water reclamation plant for brochures.
*This lesson is part of a larger unit.
Feedback to Students
Students will be required to present their filter design after testing. In their presentation they should include their filter design and an explanation of their reasoning for the design. They will share with their classmates their plans for improvement on their design to produce the safest drinking water.
Rubric for assessment of water clarity attached.