Electric Circuits
Lesson 9
Hidden Circuits
Students use their knowledge of conductors and circuits to find hidden circuits.
3. Lesson Set-up and Management
4-5 PS3A Energy has many forms, such as heat, light, sound, motion, and electricity.
4-5 PS3B Energy can be transferred from one place to another.
4-5 PS3E Electrical energy in circuits can be changed to other forms of energy, including light, heat, sound, and motion. Electric circuits require a complete loop through conducting materials in which an electric current can pass.
4-5 APPC Problems of moderate complexity can be solved using the technological design process. This process begins by defining and researching the problem to be solved.
4-5 APPD Scientists and engineers often work in teams with other individuals to generate different ideas for solving a problem.
- Students use problem solving skills to determine a way to systematically find the hidden circuits.
- Students use their circuit testers and experience with conductors to find hidden circuits.
- Students apply math problem solving skills.
3. Lesson Set-Up and Management
Materials:
- Organize the hidden circuit boxes where students can easily access them.
- If you are constructing your own hidden circuit boxes, note that a minimum of 3 hours is needed to construct them. If you get your kits from a refurbishment center and the boxes are already made, check to make sure that all circuits are complete and the wires are secure.
- Have a model circuit tester available to demonstrate for students.
 |
 |
| Testing the hidden circuit box and recording data | Creating the table to record results of testing. |
Student Management:
- Have students discuss and share their ideas with a partner after the first bullet on Procedure step 3
- Add a step after to Procedure step 7: have students record solutions for each box in their notebooks.
- Have students share how they recorded their strategies.
- The wires sometimes need to be moved around on the brads to get a good connection; demonstrate this for students before they begin. Students are often unable to find a complete circuit, often due to how they are placing the wires on the brads.
- This is a good lesson to focus on the technological design process. The problem is that there are hidden circuits in the boxes. Students need to develop a solution to this problem. The steps they will take can also be recorded in their notebook.
- If you are planning on keeping some circuit boxes out for students to continue testing (as in the Extension science activity), but have students who have not completed testing all the boxes, have students group up with others who completed the same circuit boxes. Essentially, students are completing the second part of step 1 in the Final Activities section, this is just not completed whole-class.
Writing Support:
- Focus Question: What systematic test can you use to determine which brass fasteners are connected by wire?
- Have students show their strategy in their notebook numerically and record results for each box they try.
- Have students record responses to the following prompts in their notebooks: In this lesson I learned…, A circuit tester is…, and The best way to solve the problem of finding the possible connections was….
Math Support:
- This lesson presents a good opportunity for students to use their math problem-solving strategies to systematically test the system.
- Have students use a charting method to keep track of the brads they have tested; this allows them to collect data on the combinations that were circuits, as well as those that did not result in a complete circuit.