Posted by: Steven Fowler 10/15/2009 1:13:14 PM
Title:	Microbiology Design Challenge
Grade Level:	High School
Subject Area:	Science
Lesson Time:	250 minutes for classroom activities and 250 minutes for homework
Introduction:	Students will be asked to design a solution for obtaining clean drinking water in undeveloped countries.   The product must cost less than $5. 00 retail and be locally marketable.   (Note: this price may be changed by individual teacher. )   The product must be portable so an individual can carry it.   The product must eliminate pathogens both by size and by a chemical process.   The “ drinking straw” will be presented as an idea for the students.
Standards:	Science Standard 5. Understands the structure and function of cells and organisms Standard 9. Level III. Understands the sources and properties of energy 11. Understands the origins and environmental impacts of renewable and nonrenewable resources, including energy sources like fossil fuels (e. g. , coal, oil, natural gas) Technology Standard 4. Understands the nature of technological design
Objectives:	Students will be able to: describe the water conditions of the “ other 90%” analyze the impact of microorganisms in the environment describe the different sizes of microorganisms responsible for disease analyze different types of microorganisms and their defining characteristics describe pathogenic relationships in host/microbe interactions
Resources:	A general microbiology textbook is required.   As this design task is specifically for a microbiology class, a textbook is assumed. If a textbook is not available, the Internet could serve equally well.
Materials:	Materials will vary depending on the design and whether the design is articulated using an actual apparatus or a drawing, etc.
Vocabulary:	No additional vocabulary is needed beyond what is required for a microbiology course.
Procedures:	(Note: The following is based on “ Notes on Design Based Learning” by Meredith Davis. ) 1. Review the challenge : Students will be asked to design a solution for obtaining clean drinking water in underdeveloped countries.   The product must be affordable and locally marketable to ensure ownership by the community and the longevity of its use and benefits.   The product must be portable, so an individual can carry it.   The people targeted for this device must be identified.   War is a large contributor in displacement of people around the world.   A permanent water treatment apparatus is not effective for refugees who are on the move fleeing war.   A portable device would be needed.   The product must eliminate pathogens by size and by a chemical process, because viruses are too small for filtration and chlorine may not be effective against larger protists.   Thus a two-step process may be required.   The “ drinking straw” will be presented as an idea for the students. 2. Investigate the problem or opportunity : Students will be assigned to read the chapter on environmental microbiology in their textbook.   Most textbooks include a chapter that covers water pollution and lists human pathogens transmitted by water.   Analysis of the range of organisms responsible for disease will emphasize the magnitude of the challenge.   Students should not overlook the importance of understanding their target audience.   Again, the Internet can replace the textbook. 3. Frame or reframe the problem : Now that the students have a background on the problem and the target group, they need basic information to create the criteria for a personal instrument to remove microbes from drinking water.   At this point the chapter on sterilization and disinfection needs to be read by the students.   A class discussion will follow the reading.   The instructor needs to direct the discussion towards antimicrobial chemical agents and their mechanism of action, reminding the students of the effects of such agents on human consumption. 4. Generate possible solutions : Students will be divided into groups of four.   The groups will be asked to brainstorm possible solutions.   A physical copy of the ideas must be produced at the end of the session.   This could be a model, sketch, or writing. 5. Edit and develop ideas : Following feedback from the instructor, students should choose the best idea(s) and develop prototypes.   Again, these could be presented in various forms such as a physical model, a drawing or sketch for development, or writings.   Some visual model should be encouraged, for maximum effect, by the instructor. 6. Share and critique : Groups will informally present ideas to each other.   Each group must give feedback to the presenting group either orally, in written form, or through a model of their own.   This should be emphasized by the instructor as one of the most important steps.   Encourage constructive criticism at every step.   This could be done during the fifth step as well. 7. Finalize the solution : Groups should reconvene and consider the criticism from the other groups and finalize their ideas.   Groups will prepare to present their final idea for a formal presentation. 8. Articulate the solution : Groups will formally present their ideas to an outside group of judges.   Judges could be teachers from different departments throughout the school.   For instance, an art teacher, a social studies teacher, a business teacher, and another science teacher.   The art teacher could judge the design, the social studies teacher could address the issues of the target group, a business teacher could evaluate the potential for marketing, and the other science teacher could address the efficacy of the device.
Assessment:	A formal rubric for evaluation of the product is discouraged.   Judgment of the final product is too subjective and based on the imagination or lack thereof of the evaluator.   The microbiology objectives could be assessed through any means that already exist in the curriculum.
Enrichment Extension Activities:	The ultimate extension is the development of the device.   Its efficacy could be tested, the idea could be patented, and the product could be marketed.   Ultimate evaluation must be left to the target group.   Is the device useful?  Is it needed?  Does it work as designed?  Is it worth the marketed price?  The “ across the curriculum” component should be obvious here (e. g. art, social studies, and business). The teacher could develop a method to present an understanding of the target group.   But here again, that would be biased by the understanding of the target audience by the teacher.   Understanding the target audience is subjective and biased.   Many have claimed understanding of a people and what is best for them throughout history (read imperialism).   Let the students come to their own understanding.   Who is to say they are wrong?
Teacher Reflection:	N/A.
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