Energy, Machines, and Motion
Part Two: Machines
Lesson 16: Machines Assessment: A Technological Design Challenge
Students use what they have learned about machines to design a system that will enable a small motor to lift a K’NEX™ sled. Students work in teams in a design challenge to lift a piano a distance of 0.10 meter using a motor and the machine of their choice
Focus Question: How can simple machine concepts (forces, work, and mechanical advantage) be used to enable a small motor to lift a load?
3. Lesson Set-up and Management
EALR 3: Application
Core content: Science, Technology, and Solving Problems
6-8 AAPB Scientist and technological designers (including engineers) have different goals. Scientist answer questions abut the natural world; technological designers solve problems that help people reach their goals.
6-8 AAPD The process of technological design begins by defining a problem, identifying criteria for a successful solution, followed by research to better understand the problem, and brainstorming potential solutions.
6-8 AAPE Scientist and engineers often work together to generate creative solutions to problems and decide which ones are most promising.
6-8 AAPF Solutions must be tested to determine whether or not they will solve the problem. Results are used to modify the design, and best solution must be communicated persuasively.
- Students develop a solution to a technological design challenge.
- Students test their ideas, interpret data collected and evaluate their solutions.
- Students communicate the results of their design solution to others.
3. Lesson Set-Up and Management
Materials:
- Students will need access to either Student Sheet 11.1, 12.1 or 13.2 depending on the machine they choose in their technological design.
- Students will need the rubric Inquiry Master 16.1 as a scoring guide for their assessment.
- Students will also need Student Sheet 16.1a and 16.1b for the parameters of their design challenge and the reflection of their final outcomes.
- Students will choose the incline plane, pulley or lever along with a motor and three batteries in series to lift the sled they built in Lesson 8. Have a place where students can gather the materials they will need.
- Make sure batteries are fully charged and motors are in good working condition.
- Make sure motors are in good working order.
- Set up for the materials could be partially set up from group to group to save time. This would include having pulleys, inclined planes and levers attached to pegboard systems.
Student Management:
- Students do not have access to the illustrations of how their
system might look. For those groups who are struggling a quick peak at
the set up shown in the Teacher’s Edition often will direct them in
the right direction.
- Students will evaluate their solution to the design challenge with Student Sheet 16.1b. Consider having groups report their findings to the class.
- Some groups will finish much quicker than other groups. The groups
choosing the incline plane tend to finish first and then the pulley. If
teams finish early you can challenge them with additional constraint of
using the smallest effort distance possible to lift the load.
- Some groups experience difficulty making the lever work well enough to lift the piano. If this is the case tell the students all is not lost, suggest to students how they might modify the system to get the lever to work?
Writing Support:
- Students can draw their machine-and-motor design they created in
Lesson 16. Consider using a half sheet of graph paper. Students are
more inclined to make their drawings larger and fill up their page if
the paper is a more manageable size. Be sure to have students label
the important parts of the system.
- Students could create a list of items that they had to troubleshoot. This creates a relationship of the processes scientist go through in the design process.
- Student Sheet 16a and 16b could be pasted into their notebooks after completion of the inquiry.
Reading Support:
- There are four reading selections to support students in this lesson. The first “Science and Technology” describes the differences between scientific research and technological design.
- “Technology—It’s Not Just Computers” explains the design process.
- The final two readings apply the design process to two engineering feats, the Chunnel linking England and France and the Egyptian Pyramids.
Math Support:
- Students calculate the mechanical advantages of their designs they have created in Lesson 16.
- Students calculate the efficiency of their designs.