Examining Infiltration Rates of Various Soil Types and the Scientific Method An Inquiry Based Project

Transcription

1 Purdue GK-12 Lesson Plan Examining Infiltration Rates of Various Soil Types and the Scientific Method An Inquiry Based Project Purdue University GK Lead developers, instructors and contacts: Amanda Deering Purdue GK-12 Fellow Susan Nail Klondike Middle School

2 Table of Contents 1. Overview...Page 3 2. Objectives..Page 3 3. Indiana Standards Met.Page 4 4. Methods..Page 6 5. Scope. Page 8 6. Evaluation.. Page 9 7. Comments and Reflections. Page References.Page Worksheets and Handouts..Page 11 2

3 1. Overview This lesson is an inquiry based project that allows the students to better understand the scientific method by examining the rates of infiltration for various soil types. The unit is inquiry based in that the students were allowed to design their own experiments to test the question of which soil type had the greatest rate of water infiltration. The students were first taught about the water cycle and how water is able to move through various types of soil and some of the factors that can affect this process. A significant amount of time was then used to introduce the principles underlying the scientific method and to stress the importance of the process. We thoroughly covered with the students the aspects of constructing a good scientific experiment, such as the importance of controls and replicates in data collection, and we later reinforced these concepts as the students were designing their own experiments. The students worked in small groups to formulate their hypotheses and then began working on developing an experimental protocol in which to test their hypothesis. Some general equipment, such as aluminum cans and stop watches, as well as any other additional equipment that a group thought they might need to perform their experiment, was provided to the students. Each final design was examined to ensure that the experiment followed the guidelines of the scientific method. The students then collected their data and were responsible for the format in which they collected and eventually analyzed this information. As individuals, the students then took their data that they collected as a group to their respective math class to construct a graph that would best represent the data they collected. As before with designing the experiment, we did not tell the students a specific format in which to construct their graphs, but allowed them to discover what would be the best way to represent their data. The students then went back to their groups and decided which graph was the best representative of their data for their oral presentations. They then presented to the class the design of their experiment, the data they collected, and explained why they accepted or rejected their original hypothesis. This aspect of the lesson stressed the importance of the ability to clearly communicate to others the information that is collected from an experiment. 2. Objectives The objectives for this lesson were to allow the students to have: A better understanding of the scientific method An interdisciplinary collaboration between math and science Improved group work and communication skills The main objective for this lesson was to allow the students to better learn the scientific method. Using an inquiry based lesson, the students were able to formulate their own hypothesis, determine which variables were important to test their hypothesis, design an experiment in which they collected data, analyze the 3

4 data to determine if their hypothesis was supported or rejected, and present their results and conclusions to the class. The overall process gives the students the opportunity to observe the importance of the scientific method in science. In addition, it was our goal to make this unit interdisciplinary between math and science by having the students construct graphs following instruction in their math classes. We felt this would help the student understand the interdisciplinary connections that are inherently present between the two disciplines. We also felt that having oral presentations were very important because having proficient communication skills are essential to a successful career in any field, particularly science. Having the students work in groups fostered collaboration between the group members to formulate the finished product that was to be presented to the class. The presentation helped the students learn how to clearly present their information to others so that they were able to understand the experiments that the group preformed and the results they obtained. 3. Indiana Standards Met Standard 1 The Nature of Science and Technology Students further their scientific understanding of the natural world through investigations, experiences, and readings. They design solutions to practical problems by using a variety of scientific methodologies. The Scientific View of the World Recognize and explain that when similar investigations give different results, the scientific challenge is to judge whether the differences are trivial or significant, which often takes further studies to decide. Scientific Inquiry Explain that what people expect to observe often affects what they actually do observe and provide an example of a solution to this problem Explain why it is important in science to keep honest, clear, and accurate records Describe that different explanations can be given for the same evidence, and it is not always possible to tell which one is correct without further inquiry. 4

5 Standard 2 Scientific Thinking Students use instruments and tools to measure, calculate, and organize data. They frame arguments in quantitative terms when possible. They question claims and understand that findings may be interpreted in more than one acceptable way. Communication Skills Incorporate circle charts, bar and line graphs, diagrams, scatterplots, and symbols into writing, such as lab or research reports, to serve as evidence for claims and/or conclusions. Standard 5 The Mathematical World Students apply mathematics in scientific contexts. They use mathematical ideas, such as relations between operations, symbols, statistical relationships, and the use of logical reasoning, in the representation and synthesis of data. Numbers Demonstrate how a number line can be extended on the other side of zero to represent negative numbers and give examples of instances where this is useful. Shapes and Symbolic Relationships Illustrate how lines can be parallel, perpendicular, or oblique Demonstrate how the scale chosen for a graph or drawing determines its interpretation. Reasoning and Uncertainty Describe that the larger the sample, the more accurately it represents the whole. Understand, however, that any sample can be poorly chosen and this will make it unrepresentative of the whole. 5

6 4. Methods The lesson began with an introduction to the water cycle: Various students were allowed to come to the board and draw pictures of things they thought were either directly involved with the water cycle (such as water evaporating from an ocean) or things they felt could affect the water cycle (such as animals and humans). With some guidance, the students were able to draw a complete water cycle on the board. We then discussed each aspect of the water cycle using the information that is available to the students in their 7 th grade Science textbook (see Chapter 7, pages ). In addition, we did stress the importance of the process of infiltration on the water cycle so the students could have a better understanding of the process to help them in the design of their future experiment. The following diagram was used to explain how the processes of evaporation, condensation, and precipitation interact with each other to form the water cycle. The different aspects of the water cycle were discussed and any changes that needed to be made to the previous class water cycle diagram were made. 6

7 Following the introduction to the water cycle the students began designing their experiments: The students were first presented with the research question of Which soil type has the fastest rate of infiltration? The students were put into groups (approximately 4 students in a group) and were then taken outside to examine the location of where they would do their experiment and what soil types would be available to them in this location. In the area outside of the school, the students had mulch, gravel, grass, cement, and rocks as potential soil types that they could test (this could vary depending on the outside conditions around the school). The students were brought back into the classroom and given the following equipment with which to design their experiment: 2 aluminum cans with the ends removed, a stop watch, a graduated cylinder, a beaker, a ruler, and a medium size plastic container. Using this equipment, and any additional materials that each group thought they might need to perform the experiment, the students designed how they were going to test which soil type had the fastest rate of infiltration. Most groups had differing designs and each written design was collected and checked only to ensure that the methods of the scientific method were followed (i.e. were the proper number of replicates performed?). The students also had to use the information that they knew about infiltration to develop a hypothesis of which soil type had the fastest rate of infiltration. They had to write down what their hypothesis was and ultimately have to show whether the data they collected supported or was inconsistent with their original hypothesis. The following day the students went outside and collected their data. They worked in their individual groups and most split the various tasks that were present during the data collection process among the group members. They recorded the data they collected on an outline of a data sheet (see worksheet section) that was provided where the students had to write in the soil types that they actually were testing. The next day, the students took their data sheets to their math class where they talked about the different types of graphs that are available, as well as the importance of constructing a graph that represents their data the most accurately. The students were not given instruction on which type of graph they should make, but were allowed to make the graph that they thought would be the best to show the data that they collected. Most of the graphs were hand-drawn, however, some students were taken to the computer lab so they could construct their graphs using Excel. The next exercise was done to help the students learn how to formulate their own research questions: We had the students complete a Built Environment Survey (see handout in Worksheets section). We took the students outside around the school and had them answer several questions regarding specific conditions that they were able 7

8 to observe. They had to answer questions regarding weather conditions, types of buildings present, amount of observable green space, and kinds of animals present. They then took the survey home and answered the same questions regarding the area in which they live. Using the observations that they made of the various areas, we had them formulate three potential research questions they could ask about each area. They also had to think about why knowing this information would be important and answer the question of Who Cares? for each question. We felt this exercise helped the students better understand the scientific method by allowing them to experience the importance of developing potential research questions following the collection of many observations from a given area. The students then prepared for their oral presentation: The following day, the students returned to their groups and compared their individual graphs with that of their group members. They then selected the best graph to present to the class. The students drew this graph on an overhead for their presentation and discussed how they were going to present the data to the class. There were several requirements that the students had to fulfill during the oral presentations (see Evaluation section) and each was given a breakdown of how the presentations were going to be graded before they had to present to the class. 5. Scope The class periods are approximately 40 minutes long and the following is a breakdown of how the lesson was presented and implemented. The lesson was continuous throughout the 6 days. Day 1 Discuss the water cycle o Have students draw their interpretation of the water cycle on the board. o Show examples of the actual water cycle and discuss variations between their drawings and the presented diagram. o Take students outside and select various spots to test in their experiment Day 2 Present research question to the students o Have the students formulate hypotheses o Design experimental protocol 8

9 Day 3 Perform the experiment and collect data Day 4 In Math class, construct individual graphs o In Science Outside to examine other potential environmental studies o Perform the Built Environment Survey with the students Day 5 Organize project for oral presentation o Analyze individual group members graph and decide on graph to present to the class o Draw conclusions o Decide on outline for the presentation Day 6 Present results to the class 6. Evaluation Infiltration Inquiry Project Grading Criteria -The following outlines the requirements and grading for the Infiltration lesson (For the grading sheet used, see the Worksheets section). Requirements: 1) Design an experiment showing the rate of water infiltration in different soil types 2) Conduct the experiment and graph the results 3) Draw conclusions from the results 4) Give an oral presentation about your experiment, results, and conclusions Procedures and Information: Experiment Design: A question, hypothesis, and materials/procedures should be included. The control and variables should also be identified. Graph: You will do an individual graph in math class and then either use a group member s graph or create a new graph for your presentation to the class. The graph should have a title, labels on each axis, consistent intervals on each axis, as well as a key. Neatness will also be important. 9

10 Oral Presentation: Each group member will present a part of the project. Your presentation should include your experiment conducted, data collected, conclusions as supported by the data, applications of your project (who cares?), and anything you would do differently in the project. Job Performance: You will be evaluating yourself as well as your group members in this project. Did everyone contribute? Project Grade (Out of 100 points possible): 1) Design of experiment 20 pts 2) Graph 20 pts 3) Conclusions 10 pts 4) Oral Presentation 20 pts 5) Application, errors, Job Performance 30 pts 7. Comments and Reflection This inquiry based lesson was a valuable introduction to allowing the students to examine the scientific method. I think many of the students had a very hard time accepting the inquiry based approach that we used to teach this lesson. The students kept turning to us to tell them exactly what they were supposed to do and I believe many of them found it somewhat frustrating at times when we didn t have an answer and encouraged them to formulate ideas on their own. I think in the end, however, all of the students learned a great deal from the experience. They not only learned about the scientific method, but also had the opportunity to experience working with other students and presenting the information they collected in a scientific format. We also addressed the issue of making sure that all group members participated by having a portion of each individual grade come from the evaluation of the other members of their group. This ensured that each person worked in the group and that their participation to the group effort was valuable. Overall, the students did very well with this lesson and we felt having this knowledge greatly helped the students develop their projects for science fair. This lesson was new to the existing curriculum and will be continued in subsequent years due to the many positive experiences the students gained from the lesson. 8. References Textbook: Glencoe Indiana Science, Grade 7, 2005 Edition. 10

11 9. Worksheets and Handouts Built Environment Site Survey Name: Hour: Directions for Completing the Survey Complete the survey for each site based on what is visible within a 100-yard (length of a football field) radius. Be as detailed and consistent as possible in recording your observations at each site. The goal is to get a general overview for the urban environment and identify possible environmental investigations (research questions). Site 1 Conditions: Weather Conditions Past 24 Hours Temperature: Sky Conditions: Sunny Partly Cloudy Cloudy Precipitation: Snow Heavy Rain Steady Rain Light Rain None Wind: Strong Wind Gusty Wind Light Breeze Calm Current Weather Conditions Temperature: Sky Conditions: Sunny Partly Cloudy Cloudy Precipitation: Snow Heavy Rain Steady Rain Light Rain None Wind: Strong Wind Gusty Wind Light Breeze Calm General Description of Community Population: >100,000 99,999-50,000 49,999-25,000 24,999-12,000 <12,0000 Classification: Urban Suburban City Town Rural Economic: Major Economic Service Agricultural Limited Economic Site 2 Conditions: Weather Conditions Past 24 Hours Temperature: Sky Conditions: Sunny Partly Cloudy Cloudy Precipitation: Snow Heavy Rain Steady Rain Light Rain None Wind: Strong Wind Gusty Wind Light Breeze Calm Current Weather Conditions Temperature: Sky Conditions: Sunny Partly Cloudy Cloudy Precipitation: Snow Heavy Rain Steady Rain Light Rain None Wind: Strong Wind Gusty Wind Light Breeze Calm 11

12 General Description of Community Population: >100,000 99,999-50,000 49,999-25,000 24,999-12,000 <12,0000 Classification: Urban Suburban City Town Rural Economic: Major Economic Service Agricultural Limited Economic Site Survey Parameter Site 1 Site 2 Time of Day Site Location and General Description Start: Stop: Start: Stop: Green Space (Type and estimated amounts) Built Environment Type of Building, Size, Composition and Condition of Buildings %Grass: % Barren Ground: % Trees: % Other: (Total must = 100%) Type: Size: Composition: Condition: %Grass: % Barren Ground: % Trees: % Other: (Total must = 100%) Type: Size: Composition: Condition: Type = Commercial, Residential, or Industrial Size = # of Stories Composition = Brick, Concrete, or Wood Condition = Very Well Kept, Maintained, or Dilapidated People: People: People, Use and Patterns (Patterns = Roads, Sidewalks, Walking Paths) Use: Patterns: Use: Patterns: Traffic Routes Condition and Use Size of Road: Composition: Condition: Size of Road: Composition: Condition: Use: Use: 12

13 Parameter Site 1 Site 2 Types of Natural Elements Ex: Birds, Mammals, Insects, Reptiles Open Spaces Ex: Parks, Trails, Vacant Lots, Playgrounds, Benches, Lawns Environmental Conditions Ex: Shade, Sun, Wind, Humidity, Water Streetscapes Ex: Fire Hydrants, Sewers, Utility Poles, Electrical Lines, Gas Lines, Sanitation Devices, Water Lines Evidence of Human Impact on the Environment Ex: Litter, Noise, Light, Odor, Smog POTENTIAL RESEARCH QUESTIONS: (REMEMBER: These questions should reflect the results from your site survey. For each question make sure to include why knowing this information would be important = WHO CARES!) Site #1: 1) WHO CARES? 13

14 2) WHO CARES? 3) WHO CARES? Site #2: 1) WHO CARES? 2) WHO CARES? 3) WHO CARES? 14

15 DATA SHEET FOR INFILTRATION EXPERIMENT NAME: HOUR:_ GROUP MEMBER S NAME: SOIL TYPES TRIAL #

16 INFILTRATION PROJECT GRADE SHEET Name: 1. Experiment Design (20 Total) Question (5) Hypothesis (5) Methods (10) o Materials listed o Procedures given in number order o Control & variables identified 2. Graph (20 Total) Title (2) Labeled axis (4) Standard Intervals (6) Key Provided (3) Neatness 3. Conclusion (10 Total) Do you accept or reject hypothesis? Does your data support conclusions? 4. Oral Presentation (20 Total) Voice Loud and clear (3) Eye contact (2) No disturbing mannerisms (2) Organization (5) Transition between speakers (3) Understanding of project (5) 5. Application Who Cares? (10) 6. Anything done differently? (10) 7. Job Performance (10) TOTAL 16