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This module is designed to be completed in approximately 23 class sessions. Class sessions are intended to be 45 minutes in length. Timing may need to be adjusted for class sessions of different length.

 Periods 1-3: Focusing discussion on the problem context

The problem. In order to focus and engage your students, discuss with class that among the common power sources, primary batteries are the most expensive. For example, AAA cell's energy cost is about $890 per kWh, which is 8900 times more expensive than the cost of electricity we pay at home. In reality, the actual cost is even higher if the environmental cost is properly considered. Ask the following question: " How can we design a safety light system that has minimum environmental impact?" After providing " wait time" for the class to think, elicit and record on the discussion board a number of possible ideas and briefly examine the feasibility of each with the class. If the class fail to mention solar photovoltaic charging as a way to power the safety light system, lead to that direction by asking, for example, how do astronuts generate electricity in the space shuttle. They should respond with such examples as solar cells, fuel cells, etc.

Tell the class that they are going to concentrate on solar cells because they are the cheapest and have the least environment impact.

The challenge.

Redirect students to the WEBTECH pages. As you go through the contents together, present the challenge in a manner that will motivate them. Discuss briefly the What You Will Do, Problem Context, and Materials Needed sections.

 Period 1 -3: Organizing for Informed Design

Informed design. Elicit from students what they know about good design and who engages in design. Ask for examples of good design and poor design. Tell the class that completing a series of KSBs will help prepare them for addressing the design challenge they face. Then introduce KSB #1:The Informed Design Cycle and provide time to read it. The information in KSB#1 should be referred to often as groups work on the design challenge. The Informed Design Cycle loop can be particularly useful to the students as they chart their progress using a Design Journal (or Design Activity Folio). Like professional engineers, they will find themselves using the loop in an iterative way rather than in a linear way.

Discuss the informed design cycle and stress that although design is normally informed by the designer’s current knowledge, completion typically requires access to new knowledge. Discuss the need to research what solutions exist to solve this design challenge, and how reaching an optimal design solution requires meeting specifications, working within constraints, and making trade-offs.

Student requirements.

Discuss the student requirements after determining whether you will expect the students to use the Design Activity Folio (DAF) or the Design Journal. Help students see that either of these devices allows them to document progress as they complete literature searches, factor investigations, and Knowledge and Skill Builders (KSBs). Describe the requirement that each student submit a Design Report and each group make a class presentation at the conclusion of the module. Explain that the report and the presentation will be based on information recorded in the Design Journal or DAF. Alert them that the presentations should be multimedia and should detail their design process and results. Help them see that such a presentation summarizes work completed in researching, collecting, and analyzing data; developing models; improving designs; and making refinements.
Describe multiple forms of media (for example, powerpoint presentations, color overheads, videos, computer animation) that they might use to enhance their presentations. Assure them that when classmates ask probing questions and challenge group findings at the end of presentations, they are mirroring proceedings that are common at science conferences.

Assigning groups.

Talk with some of the students ahead of time to see how experienced they are at working in cooperative groups. Assign small working groups; three is ideal. Monitor groups throughout the module.

 Periods 4-16: Coordinating student progress

Coordinate work by individuals.

Plan opportunities within this module for students to revisit their initial understandings by providing experiences with new phenomena that contradict their stated perceptions. Unless individuals get to actively process such contradictions, they may fail to grasp the new concepts and then may revert to their preconceptions. Help individual students make the connection between carefully documenting information as they proceed and well-written reports and presentations at the end. Note that a student displaying unacceptable behavior may be doing so because other members of the group do not value what he/she says. Get to know the strengths
of such a student and try assigning roles for all members of his or her group. Give thestudent a role that features a personal strength and inform the group ahead of time that this person is known to do that task well.

As the work becomes more technical and cerebral, some students will begin to complain that they are doing all the work while others loaf. Citing examples from your own experience, explain to such individuals that the best way to learn something is to teach it to others. Remind the group that it is essential that all members of a cooperative group understand all ideas and steps along the way. Conduct frequent oral checks to see that each student has adequate understanding before the group moves on in its work.

Sharing.

Convene the large group one or more times to share results of individual and group investigations. Invite students to listen critically to one another and facilitate a discussion of how this knowledge can be used to inform their design of a safetylight system. Continue to work as a facilitator as students work in their groups to create alternative designs. Check to see that each group understands that its solution must address the specifications and constraints. Remind each group to make decisions and select design components based upon their investigations and their understanding and application of MST principles. You might want the groups to develop a rating system to determine which alternative design is preferred.

Planning and constructing.

Continue to work as a facilitator as groups select their preferred alternative and develop plans for construction. Facilitate a discussion of trade-offs that are made in the search for an optimal design solution. Encourage groups to identify and model functional design elements and construct their working prototype.

Testing.

Bring students together as a large group and discuss ways in which each group might test their design. Facilitate small group development of testing and evaluation procedures. Bring the entire group together to compare results. Encourage student groups to carefully review the work of other groups to gain ideas that might inform a redesign. When redesign is discussed, continue to direct students’ attention to how the understanding and application of MST concepts can guide improvements.

 Periods 17-19:

Summing up progress on the learning goals Design report. The reports are one of the major opportunities for you to determine whether individuals have attained your goals for this module. Continue to work as a facilitator as groups document their progress and share results. Explain that each student must submit a Design Report. Assist individuals in structuring and writing their Design Reports. The Design Report should include a discussion of redesign with justifications for the redesign decisions. Provide students with the Design Report guidelines. As you introduced this mod you told students that careful documentation in the Design Journal leads to a well-written final report later on. For individuals who have
trouble writing, check their documentation frequently along the way to ensure that they will have a source of information adequate to generate a report.

 Periods 20-23:

Group presentations. Discuss with the class what is considered proper and expected deportment during group presentations. Address the need to use a variety of media to support the presentation. Review and distribute the presentation guidelines