Content Standard F:
Science in Personal and Social Perspectives:
Science and Technology in Society

Scientists and engineers help design and
implement technology that affects the quality of life.
The process of designing and implementing
technology is sequential.

To control dental plaque, students will design a
toothbrush, implement the proposed design,
evaluate the product, and communicate the process of the technological design.
To model how scientists and engineers collaborate to accomplish a goal, students will work together.

Cross-Curricular Connections:

Math:
• Drawing to scale, measuring
• Estimating
Language Arts:
• Writing and communicating orally
• Labeling
Arts:
• Designing
• Drawing
• Constructing graphic organizers
Health:
• Understanding dental plaque

Communicating
Problem Solving
Inferring
Predicting
Analyzing
Modeling

Materials:

Per Group:
several different types of toothbrushes to illustrate current tooth brush technology (Local dentists may donate the tooth brushes.)
drawing paper
rulers
various materials provided by students with which to make their toothbrushes

Procedure:

Session 1

1. Use the background information to introduce the concept of biofilms and their role in dental plaque formation. Show the video on biofilms. Start and stop the video during class discussion, as needed, paying particular attention to the segment on dental biofilms. (Use the National Science Education Standards to guide a class discussion of science and technology) Identify present day technological solutions to the problem of dental plaque caused by biofilms.
   
   
2. Present student teams of 3-4 students with the challenge of designing a better toothbrush to control biofilms that cause dental plaque. Give clear instructions for the procedures which the students are expected to follow and the criteria for design and implementation of their product. (As an alternative, students may brainstorm and develop the criteria together.) Students should be provided with an assessment rubric, timeline, and team worksheet to be filled out and returned at the completion of the activity.

Session 2

1. Student teams organize their groups, assign responsibilities, and select a name for their research team.
   
   
2. Each team brainstorms ideas to design and implement a model of a better toothbrush. Factors to consider include the nature of biofilms, the projected users of the toothbrush, cost, materials, safety, ease of use, limitations, benefits, and unintended consequences.
   
   
3. The criteria for the design:
   a. Type and size of paper to draw the design on as stipulated by the teacher (example: 1/2 sheet of poster paper).
   b. Type of media to use as stipulated by the teacher (example: pen and ink, colored pencils, markers).
   c. Drawing should be to scale.
   d. Components should be clearly labeled.
   e. Product should be named.

Session 3

1. Research teams implement the proposed design by making a scale model.
   
   
2. The criteria for the new toothbrush:
   a. Original and creative idea
   b. Practical application (Will it work?)
   c. Materials to be used to construct the actual toothbrush (Are they practical and cost-effective?)
   d. Cost to the consumer
   e. Environmentally friendly packaging
   f. Aesthetics of design (How attractive is it?)
   g. Ease of use by the consumer
   h. Suitability for the need
   i. How will it be tested prior to marketing?
   
   
3. Evaluate the completed product and make necessary modifications.
   
   
4. Communicate the process of technological design through a graphic organizer such as a Vee diagram, concept map, or flow diagram (Novak and Gowin, 1984). It should describe and analyze the product and identify the stages of problem identification, solution design, implementation, and evaluation.

Session 4

1. Research teams present their products to the class.
   
   
2. Students conduct a peer evaluation of the pros and cons of each product and provide feedback to the research teams

Suggested Discussion Questions:

Research Team Brainstorming. During ongoing assessment observe intercommunication among the team members and note the quality of their questions. Sample questions include:

What are the benefits, limitations, and unintended consequences of using a toothbrush?
What are some limitations of the toothbrush designs currently being used to remove bacterial biofilms from your teeth?
How long should one keep a toothbrush before throwing it away? Why?
What about the materials that a toothbrush is made of? Have you ever used a metal one? Why not?

Students select other types of technology used to improve personal health and research their benefits and limitations.
Student teams of four may be interested in participating in The Bayer/NSF Award for Community Innovation. Sixth, seventh, and eight graders employ teamwork, science and technology to solve community problems. Teams work under the guidance of an adult coach and 10 teams are selected as national finalists. Check out http://www.nsf.gov/bayer-nsf-award.htm
Students design an advertisement for their product. This could be for print, radio, TV, a bumper sticker, etc.
Students could also prepare a verbal presentation to convince a company to market their product.

Dentist
Dental Hygienist
Microbiologist
Research Scientist
Marketing
Engineering
Graphic Design Artist
Public Relations Expert

Assessment Procedures:

Ongoing social interaction skills may be assessed through peer and teacher evaluations.
Teacher assessment of the design should be done prior to construction of the product model.
Peer and teacher evaluation of the class
presentation of the final products should be
conducted. The products may also be displayed for parents, faculty and school visitors to view.
Students can also reflect on their experience through journal writing.