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The Water Quality Project Boston Latin Academy, Boston, Massachusetts, USA How the Unit Worked
THE TEACHING Unit Introduction
The teachers then went over the unit goals, projected from an overhead, and the main activities and expectations of this unit, and answered any initial questions that the students had. The unit website was also introduced at this time. Every lesson, the understanding goals for the day were clearly written out on the board and discussed briefly. The Unit Introduction lesson plan is available in Materials and Resources. Water Quality Testing and Standards
Aside from introducing water quality testing, this lesson served to further engage the students in the unit and help them connect to the issues of water quality through investigating and thinking about their own drinking water and the river in their neighborhood. WQ Testing and Standards Lesson plan is available in Materials and Resources The Water Quality Parameters
Below is a brief description of each test used in the Water Quality Unit
The Water Quality Tests
The students would read a handout on the parameter and answer questions for their homework, and then learn and practice the actual test in the laboratory the next day. If time allowed, the nuances of each test were discussed further. These lessons gave the students the basic skills for water quality testing and laid down the foundation for understanding the six water quality parameters. The students used this foundation later in the unit to continue expanding their knowledge and applying it to new situations. Lesson plans for each of the six water quality tests are available in Materials and Resources: Temperature Lesson Plan, pH Lesson Plan, Turbidity Lesson Plan, Fecal Coliform Lesson Plan, Total Hardness Lesson Plan Dissolved Oxygen Lesson Plan. Field Trip to Jamaica Pond
On the field trip, which took about 3 hours to complete, the student groups surveyed their site, made predictions regarding the water quality, and then proceeded to test for Temperature, pH, Turbidity, and Dissolved Oxygen. The students also collected samples to bring back to the school for subsequent Total Hardness and Fecal Coliform testing in the lab. As any field trip, this one involved a great deal of preparation and organization on the part of the teachers; even more so due to the large amount of equipment Jerry and Vasilii took with them. However, both teachers felt that it was the field trip that really "hooked" the most students and made them understand the importance of a good site survey. Despite the cold, most students were having fun, and on the end-of-unit evaluations, the field trip was voted as both the most interesting and valuable activity by the students. Field Trip Lesson Plans are available in Materials and Resources Final Project The final project asked the students to bring together and synthesize all the knowledge and skills they had acquired in the duration of the unit. The assignment was to conduct an investigation of the water quality in a river, lake, or pond of the group's choice using the six parameters studied in the unit. Aside from inviting the students to demonstrate their mastery of all the unit material and to apply their understanding to a new problem, the project had two other objectives. First, to give the students a still better idea of what real water quality work in the field would be like. Second, to allow the students to experience all or most of the elements of a science research project.
The groups then collected their samples and conducted their tests in the laboratory to test their hypotheses. The results were analyzed, and presented in a poster format. Each group used their poster to deliver a presentation to the class on their work. The project went far beyond what most school assignments expect of the students - they were expected to be independently motivated, persistent, organized, and being able to work together and coordinate their efforts outside of school (often from opposite sides of the city). At the same time the project tapped into the groups' creativity and gave the students a degree of independence that allowed them to focus on something they were really interested in. The work completed on the project ranged in quality, but most of the posters exceeded both teachers' expectations. It was evident that most students invested themselves fully into their projects, and went out of their way to obtain data and information. One student chose a pond in the suburbs of Boston that he grew up near for his study and interviewed his relatives and even some construction workers at the pond about the pond's history and current condition. Another made a trip to the office of the Army Corps of Engineers to obtain topographical maps and flood zone charts for the Charles River. Some of the results were rather telling as well. One group chose to compare the pH of surface water before and after a day of rain, and found that the pH had dropped from 6.0 to 5.0!
Lesson Plans for the final project are available in Materials and Resources Assessment The students were assessed on daily homeworks and on their project proposals, posters, and presentations. Take a look at the Final Project Lesson Plans in Materials and Resources for detailed assessment criteria. Unit Web Page The educators maintained a web page for the unit which included all lesson goals and summaries, assignments, handouts, and relevant web links. The students were encouraged to use the website regularly as a resource. Take a look at the Water Quality Website. Onto: |
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The unit began by asking the students to think about just what they understand as water quality, and what it would mean to have good quality water—first individually, and then in groups. This brought out the students' prior ideas about water quality and generated a lively discussion about just what "good water" is. The students were then asked to think about how and when has water quality directly affected them; many students recalled that when they were little the water in the Boston Harbor was of much poorer quality than today. In groups, the students thought about the ways poor water quality can affect human populations and the environment. This activity helped make the unit more generative by immediately allowing the students to look at the topic from their own perspective and to connect it to their own experience.
The second lesson began with a discussion of who, where, and how ensures that we have good drinking water in Boston. The students had done a research paper on Water Quality that asked them to look at the MWRA system, and they remembered a great deal about the city water supply. Few, however, remembered how the quality of water is ensured, and through the discussion the class established that the first step would be to test the water for "various contaminants". The relevance of water quality testing was thus established by the students themselves. The class then moved on to discuss what things we should test for, and how to make sense of our results, thus establishing the need for standards.
Next, the class looked at the projected website of the Charles River Watershed Association (CRWA). The Charles River is well known to everyone in Boston, and Jerry and Vasilii first asked the students to make predictions about the water quality of the Charles all along its length. The students were very surprised indeed when they then saw a map of the Charles that showed that not only is the Charles swimable along most of its length, but that its quality in downtown Boston is among the best. For homework, the students were asked to investigate water quality in the pipelines using MWRA on-line data. The students remained engaged throughout these lessons and most commented that they enjoyed spending so much time in the lab and the hands-on nature of the instruction.
Temperature, pH, Turbidity, Fecal Coliform, Total Hardness, and Dissolved Oxygen are the water quality parameters for this unit. These 6 parameters were chosen because they seemed to fit the objectives of this particular unit the best. The Vernier Software "Water Quality" manual as well as the Massachusetts Water Resources Authority (MWRA) manual (see references) provide several other tests to choose from. The following criteria were considered when selecting the water quality tests:
In going over each of the six tests, Jerry and Vasilii used a similar approach. Typically, at the beginning of the class the students would be asked to write down their own ideas about what a particular parameter is and its significance. The students did this individually or in groups. Most of the students had at least some understanding of what the parameters were from the research paper they wrote. The class then discussed these ideas together and arrived at the correct definition and the main reasons for why this parameter is worth testing for. The teachers then proceeded to lead the class into further discussion / brainstorming that focused on two main questions:
The field trip served as a transition between the classroom instruction, and the culminating "real-world" project in which the student groups conducted independent investigations on a water body of their choice. The students were given an opportunity to transfer their "lab" understanding of the tests into the field under the supervision of the instructors. The field trip advanced the generativity of the unit yet another step, as it made the students experience how their learning transfers to the real world - studying a pond in Boston they are all familiar with. At the same time, the field trip and the class discussion prior to it made the students think about and gave them a basic understanding of the importance of an accurate and detailed survey of the site, and of how one can explain the water quality results in terms of the water's environment.
The students first needed to select a site and conduct some background research: what's the history, what is it used for, what's around the site? Next, the students needed to conduct a thorough site survey. Based on the information acquired in their site surveys and background research, the students needed to make justified predictions about each of the six parameters. The students also needed to choose one parameter to investigate in more detail and introduce a sampling variable (i.e., time of day, distance from shore, etc.) Based on their understanding of the parameter the students needed to hypothesize how the parameter would be affected by the sampling variable. All of this information was then written up as a research proposal and discussed in a conference with one of the teachers.