1. Explain to the class that they will carry out a scientific investigation using materials on the Web. In this investigation, they will be working as members of an investigative team from the local community health department.

Throughout this activity, you will act as team supervisor for all the student teams.

2. Give each student a copy of Master 3.1, Investigative Report Form. Explain that students will use this form to record the progress of their investigation.

Each day, students will write notes about their investigation on a separate copy of the Investigative Report Form.

3. Divide the class into teams of three and direct each team to a computer. Instruct students to proceed to http://science.education.nih.gov/supplements/inquiry/student and click on “Activity 1—Unusual Absences.”

This link displays the home page of the intranet site for a fictitious community health department.

Content Standard A:
Identify questions that can be answered through scientific investigations.

4. Have students click on the link for “You have (1) New Message” and read the e-mail message from the director of the health department.

The e-mail contains an attached letter from a principal of a local school and a link to the school district’s Web site. The principal states that this past week, an unusual number of students were absent from the band class. She is concerned that the school may be facing an outbreak of flu. As members of the investigative team, students first read the letter and write a testable question (Step 5). Only then do they proceed with their investigation by clicking on the link to the school district Web site.

5. After teams have read the e-mail message from the director and the attached letter from Principal Parsons, discuss what testable questions they can ask as they begin their investigations to determine whether a health problem exists.

Content Standard A:
Different kinds of questions suggest different kinds of scientific investigations.

Students should record their testable questions on their Investigative Report Form (Master 3.1) and be prepared to share them with the class. Circulate among the teams as they work to develop their testable questions. Remind students of the aspects of testable questions listed on the board.

Students should ask questions that will help them determine whether the school absences indicate a health problem. Ideally, they should be able to answer their questions by examining the school attendance data provided at the school district’s Web site. Examples of testable questions they might ask include

• Is the number of absences in the last week more than in previous weeks?
• Are more students absent from one type of class than the others?
• Are there more absences in one school than the others?

6. After the teams have developed their testable questions, have them return to the director’s e-mail message and click on the link to the school district’s Web site. At this site, they can access attendance data for the community’s four middle schools.

The only active link on the school district’s Web site is the “Attendance Data” link.

Content Standard A:
Use appropriate tools and techniques to gather, analyze, and interpret data.

7. Once students have viewed the attendance data, explain that they need to export the data to the health department’s Web site, where the data can be displayed in graphic form. To export the data to the health department’s Web site, students click on the “Export Data” button and type “cohd.org” into the “Export Destination” box.

Students now have access to the “Data Analysis” section of the health department’s Web site. If students click on “View Data,” they can see the same data tables that are on the school district’s Web site. If students click on “Create Graphs,” they are given a menu of 16 graphs from which to choose. Students can view from one to four graphs at a time. After they have made their selections, students click on “Display Graphs” to view them. Students may also print the graphs either individually (to fill the page) or in groups of up to four at a time.

Tip from the field test: Write the export destination, “cohd.org,” on the board.

Content Standard A:
Use mathematics in all aspects of scientific inquiry.

Content Standard E:
Science and technology are reciprocal. Science helps drive technology. Technology is essential to science.

8. Instruct teams to use the graphs and data sheets to analyze the attendance data. Students should record their findings on their Investigative Report Form. Explain that they will share their results with the class later.

The graphs and data sheets provide evidence that teams will use to propose explanations for the student absences. Students should look for sudden increases in absences that might indicate a health problem and for comparisons that help them answer their testable questions. They should note the patterns they observe in the attendance data for each school. Students should observe the following:

• There was an unusually high number of absences during the last week among students in band classes at both Truman and Jackson middle schools.
• Absences among students in art and PE classes, as well as for the entire seventh grade, were not higher during the last week for both Truman and Jackson middle schools.
• Roosevelt and Kennedy middle schools had fairly constant numbers of absences throughout the last month in every category.

Tip from the field test: Remind students to record their evidence as they review the data and graphs. Help students develop their explanations. Ask, “How can you explain the evidence you have collected?”

9. Instruct teams to exit the Web site after they have completed their analyses and recorded their findings.

Content Standard A:
Develop descriptions, explanations, predictions, and models using evidence.

10. Acting as team supervisor, facilitate a class discussion to summarize the findings from all the teams. Consider which steps the investigation should take next. Guide the discussion to focus on the following questions:

• What is the reason for the higher number of absences among students in band classes at Truman and Jackson middle schools?
• If these absences are due to an illness, do band members from the two affected schools share the same symptoms?
• Have band members from the two schools been in recent contact with each other?

Students should have recorded the testable question for their team on their Investigative Report Form. When filling out the form, students should write down under “Evidence Collected” anything that they feel may have a bearing on their investigation now or in the future. The summary of findings should be included in the “Analysis and Explanation of Evidence” space. The next steps for the investigation should be phrased as a question and entered into the space on the form labeled “Next Questions.”

Content Standard A:
Think critically and logically to make relationships between evidence and explanations.

1. Explain to the class that they will continue their investigation into the school absences among band members at Truman and Jackson middle schools. Specifically, they will answer the testable questions that were developed at the conclusion of Activity 1:

• What is the reason for the higher number of absences among students in band classes at Truman and Jackson middle schools?
• If these absences are due to an illness, do band members from the two affected schools share the same symptoms?
• Have band members from the two schools been in recent contact with each other?

2. Give each student one copy of Master 3.1, Investigative Report Form. Instruct students to write the testable questions developed at the end of the previous activity in the “Testable Question” space on their form.
3. Reconvene students in their teams from Activity 1. Direct each team to a computer and instruct students to proceed to http://science.education.nih.gov/supplements/inquiry/student and click on “Activity 2: What’s the Cause?”

As in the beginning of Activity 1, the teams are alerted that they have a new e-mail message to read.

4. After reading the new e-mail from the director, the teams click on the link to the tables that list results of interviews.

Information in the tables was obtained from interviews with the students’ parents. The table for Truman Middle School shows that there were 10 students from band class absent during the past week. One student was away on a family vacation. The other nine students all have an illness that displays stomach-related symptoms. The table for Jackson Middle School lists eight absent students. One student has a broken leg. The remaining seven students have an illness that presents stomach-related symptoms.

5. Have the teams read portions of the interviews with the parents on the Web site and record their conclusions on their Investigative Report Form. They should be prepared to share their findings with the rest of the class.

Content Standard A:
Recognize and analyze alternative explanations and predictions.

The parents report the same symptoms listed in the tables. Some parents volunteer reasons for the illnesses, such as food poisoning or the flu. These conflicting reasons may confuse some students. You may point out that the reasons given by the parents are opinions and not diagnoses from a doctor, which are based on medical evidence.

6. After the teams have examined the results of the interviews and read portions of the parent interviews, have them click on the link to the calendars of school events.

Circulate among the teams as they look at the school calendars. Remind students that they are looking for evidence that will help them develop better explanations about the cause of the health problem. Make sure that students understand why they are looking at the school calendars. An illness is involved. If there are contacts between the students from the two schools, then such contacts may help explain how an illness was contracted or passed from student to student. A healthcare worker makes a subtle but important point during one of the parent interviews. The worker mentions that with food poisoning, a person becomes ill in a day or two, while a stomach virus takes about five days before the illness strikes. Students should use this information to help decide what type of illness may be associated with which activities of the band members.

7. Have students compare the two school calendars and write down their conclusions.

Content Standard A:
Think critically and logically to make the relationships between evidence and explanations.

A comparison of the Truman and Jackson middle school calendars reveals that the seventh-grade bands from both schools were together three times in the past month:

• On May 5, both bands performed at a May Day parade. Students should note that May 5 was likely too long ago to be associated with the current illness. It is interesting that the band from Roosevelt Middle School was also at the parade and yet its band members did not become ill.
• Students from the two bands were together on May 15 for a planning meeting about the upcoming Battle of the Bands.
• The bands competed at the Battle of the Bands event on May 19.

Tip from the field test: Remind students to review their evidence and explanations from the previous activity.

Content Standard A:
Develop descriptions, explanations, predictions, and models using evidence.

8. Instruct teams to exit the Web site after they have completed their analyses and recorded their findings.

9. Acting as team supervisor, facilitate a class discussion to summarize the findings from all the teams. Think ahead to the next steps for the investigation. Guide the discussion to focus on the following questions:

• Is there a common reason for the absences of the band students at Truman and Jackson middle schools?
• What are possible causes for the student illnesses?
• How could students from both bands be exposed to a disease-causing organism at the same time?
• Assuming that the students from the two bands are suffering from the same illness, when were they most likely exposed to the disease-causing organism?

Assessment:
Making a quick visual scan of the Investigative Report Forms offers a brief formative assessment of students’ progress to this point.

Encourage students to ask questions about the activities the band members might have participated in during the planning meeting and at the Battle of the Bands. Students should be concerned about activities the sick band members have in common. If not brought out by a student, call attention to the fact that people become sick about five days after being exposed to a stomach virus, while they become sick within a day or two after eating contaminated food. At this point, we can speculate that students were either exposed to a stomach virus during the planning meeting or to food poisoning at the Battle of the Bands. Students will be provided with details about band activities in Activity 3.

1. Explain to the class that they will continue their investigation into the school absences among band members at Truman and Jackson middle schools. Specifically, they will explore the activities students engaged in during the Battle of the Bands event to see whether they can pinpoint how the students became ill.
2. Give each student one copy of Master 3.1, Investigative Report Form. Instruct them to write the testable questions developed at the end of the previous activity in the “Testable Question” space on their form.
3. Reconvene students in the same teams as before. Direct each team to a computer, and instruct students to proceed to http://science.education.nih.gov/supplements/inquiry/student and click on “Activity 3—What’s the Source?”

As in the beginning of the previous activities, the teams are alerted that they have a new e-mail message to read. The memo informs the teams that a nearby community has reported that its water supply may be contaminated by bacteria that cause a stomach-related illness.

4. After reading the latest e-mail from the director, the teams click on the “Activity Tables” link that provides information about the activities that took place on the day of the Battle of the Bands event.

Content Standard C:
Some diseases are the result of intrinsic failures of the system. Others are the result of damage by infection by other organisms.

The activity tables provide information about the activities that band members from both schools participated in on the day of the Battle of the Bands event. The tables include information about activity participation by band members who became ill and those who did not become ill. This page also contains a menu that allows students to select maps that indicate the locations of each activity.

Tip from the field test: The students’ knowledge about disease transmission is limited. Make sure that they understand that food poisoning and illness from contaminated water are not contagious. However, a stomach virus can be passed from one person to another.

5. As the teams examine the activity tables, remind them also to examine the maps that depict where the activities took place. Encourage students to use the tables to compare the activities of the students who did and did not get sick.

Content Standard A:
Recognize and analyze alternative explanations and predictions. Use appropriate tools and techniques to gather, analyze, and interpret data.

From the Activity Maps menu, students can select maps that depict

• a street map that includes the locations for the various student activities,
• students from Truman Middle School who became ill and the activities in which they participated,
• students from Jackson Middle School who became ill and the activities in which they participated, and
• students from both Truman and Jackson middle schools who became ill and the activities in which they participated.

6. Instruct the teams to write down their conclusions about which activities may have exposed the students to disease. They should be prepared to share their conclusions with the other teams.

Analysis of the activity data suggests that either eating at the Cheep Chicken Hut restaurant or swimming in the lake made the band members ill.

Content Standard A:
Communicate scientific procedures and explanations.

Content Standard F:
Risk analysis considers the type of hazard and estimates the number of people who might be exposed and the number likely to suffer consequences. The results are used to determine the options for reducing or eliminating risk.

7. Instruct teams to exit the Web site after they have completed their analyses and recorded their findings.
8. Acting as team supervisor, facilitate a class discussion to summarize the findings from all the teams. Guide the discussion to focus on how the teams think the band members became ill. Ask the teams to explain their evidence and reasoning.

Students should conclude from their analyses of the activity tables that two possibilities exist: 1) students got food poisoning at the Cheep Chicken Hut and 2) students were infected while swimming in the lake. Without additional information, it is not possible to eliminate either possibility from suspicion. A third possibility also exists. Students could have contracted a stomach virus while attending the planning meeting on May 15. Explain to students that the process they followed is similar to that used by scientists conducting an investigation. Investigations do not always reach a single conclusion. They often raise more questions that need to be investigated.

9. Ask students to consider what next steps they could take to reach a firm conclusion about the cause of the student illnesses. What evidence would they like to collect?

Student suggestions may include

• visit the various restaurants and take food samples for testing,
• visit the lake and take water samples for testing,
• have the illnesses of the sick students diagnosed by a doctor,
• investigate activities (such as eating) that took place during the planning meeting, and
• survey other people (not students) who ate at the Cheep Chicken Hut or swam in the lake to see whether they also became sick.

Assessment:
Use the completed Investigative Report Forms as a summative assessment.

10. Collect from students their three Investigative Report Forms.

These forms will be used in the next activity and as an assessment tool for you.

Content Standard G:
Science requires different abilities, depending on such factors as the field of study and type of inquiry.

Student responses will vary. Bring out the idea that the investigation began with a problem that prompted the asking of a testable question.

2. Ask students, “What testable question began your investigation?”

Students will report different questions. Appropriate questions deal with whether or not the school absences noticed by the principal are unusually high. Students may have asked a question such as, Is the number of school absences in the last week more than in previous weeks?

3. Ask students, “As your investigation went along, did you ask other testable questions? What were they?” Write their questions on the board.

Students will report a number of different questions. Try to guide the discussion so that the questions are brought up in the order that they appear in the investigation. Examples of questions that students may report are the following:

• Are more students absent from one class than the others?
• Are there more absences in one school than the others?
• What is the reason for the higher number of absences among students in band class at Truman and Jackson middle schools?
• Are the absent students suffering from the same illness?
• Have band members from the two schools been in contact with each other?
• What is the cause of the disease?
• What is the source of the disease-causing organism?

4. Next, turn the discussion to the collection and analysis of evidence. Ask students, “What evidence did you collect and analyze to answer your questions?”

Students will mention various types of evidence collected.

5. Ask, “Was all of the evidence you analyzed helpful in answering your questions?”

Student responses will vary. Some will report that all evidence was helpful because it helped them answer a question or choose between alternative explanations. Other students may feel that some evidence was not helpful because it could not definitively answer their question.

6. Explain to students that they will now reconsider the evidence used in their investigation, consider what information the evidence provided, and explain how that evidence was used to answer a question or to choose between alternative explanations.

7. Give each student one copy of Master 3.12, Analyzing Evidence. Explain that they have about 15 minutes to

• consider the evidence used in their investigation,
• write down the information they learned from it, and
• explain how it helped, or did not help, them to answer a question or choose between alternative explanations.

Content Standard A:
Communicate scientific procedures and explanations.

Content Standard G:
Scientists formulate and test their explanations of nature using observation, experiments, and theoretical and mathematical models.

Assessment:
Assess students’ understanding by listening to their explanations and reasoning.

While the students are working, circulate among them and guide their progress. Some students may not understand why some pieces of evidence were included in the investigation. For example, the interviews with the parents of the sick students are necessary to confirm their reasons for absence from school.

8. After students have completed their work on Master 3.12, ask for volunteers to share their answers with the class.

As students report their answers, guide the discussion to raise the points made in the following sample answers for Master 3.12.

1. Memos from the director of the community health department

The first memo suggests a possible health problem at a local school. The second memo provides access to information about the student absences and student band activities. The third memo raises the possibility that the local water supply is contaminated.

2. Attendance data for seventh-grade students at four middle schools

The attendance data reveal that students in band classes at Truman and Jackson middle schools were absent during the past week at rates several times higher than normal. This is considered to be evidence of a possible health problem. It remains possible, however, that all or some of the absent students were missing from school for reasons other than illness.

3. Summaries of interviews from parents of absent students

Interviews with parents of the missing students confirmed that the students were indeed absent from school and supply reasons for their absences. The parent information summarized in the tables indicates that all but two of the missing students were ill with a stomach-related illness. This information rules out the explanation that students were absent from school because they were truant.

4. Transcripts from interviews with parents of absent students

The interviews with parents provide additional information about the student absences. For example, one parent states that her child has the flu while another attributes his child’s illness to food poisoning. These comments are included to suggest possible causes for the illnesses. These comments are opinions, however, and must not be treated as necessarily factual.

We also learn from the interviews that it usually takes about five days to become sick after being exposed to a stomach virus. In contrast, a person who eats contaminated food usually gets sick within the next day or two. This information becomes important when trying to decide which contacts between students from the two schools might be associated with the illnesses. For example, a stomach virus may have been contracted from sick students at the planning meeting, or stomach illness may have been spread during an activity at the band event such as swimming in contaminated water or eating contaminated food.

5. School calendars

Since the available evidence suggests that the absent students may all be suffering from the same illness, it is important to investigate whether the affected students from the two schools were in recent contact with each other. Such contacts provide opportunities for a disease-causing organism to pass among the students. Assuming that eating is involved, such shared experiences are also consistent with illness resulting from food poisoning.

A comparison of the school calendars reveals that band students from the two schools came into contact with each other three times in the past month. The first occasion was the May Day parade on May 5. It is unlikely that the illnesses resulted from this contact because it occurred so long ago. Further supporting this view is the fact that the band from Roosevelt Middle School also attended the parade but its students did not become ill.

Students from the two bands were also together for the Battle of the Bands planning meeting held on May 15. It is possible that a student with a stomach virus spread the illness to others at this meeting. Assuming that students would become sick five days later, they would be absent from school starting on May 20, which is what was observed. Students from the two schools also were together at the Battle of the Bands event on May 19. It is possible that students ate contaminated food at the event and became sick the next day.

Content Standard F:
The potential for accidents and the existence of hazards imposes the need for injury prevention. Important personal and social decisions are made based on perceptions of benefits and risks.

6. Student activity tables

At this point, the most likely explanation for why the students became ill is that they either contracted a stomach virus at the planning meeting or got food poisoning at the Battle of the Bands. These tables provide information about which students participated in which activities at the Battle of the Bands. This information may help identify a source of exposure to a disease-causing organism. Information from the tables reveals that the majority of students who became ill ate at the Cheep Chicken Hut restaurant and swam in the lake. This means that students may have eaten contaminated food at the restaurant. It also raises the possibility that students became ill by swimming in contaminated water. Consistent with this new possibility is information contained in the third memo from the health department director, which mentions that a nearby community suspects that its water supply is contaminated with bacteria that cause a stomach-related illness.

7. Activity maps

These maps show where the various activities associated with the Battle of the Bands event took place. The final map depicts the activities attended by students from both schools who later became ill. This information suggests that the illnesses were related to eating at the Cheep Chicken Hut restaurant or swimming in the lake.

9. Explain that in the next lesson, students will continue in their roles as members of the investigative team. They will take charge of another investigation dealing with a community health problem.