Lesson 4: From Simple Circuits to Engineered Systems – Analyzing Circuit Boards

• How do simple circuits scale into complex systems?
• What are traces and why are they important?
• What role do resistors, capacitors, and other components play?
• How is electricity controlled rather than simply allowed to flow?
• Why is regulation necessary in digital devices?

Circuit board
Trace
Pad
Resistor
Capacitor
Inductor
Diode
Integrated circuit
Processor
Regulation
Stabilization
Signal
Component

HS PS2-6
Communicate scientific and technical information about how molecular-level structure influences designed materials.

HS ETS1-2
Analyze a complex real-world problem and evaluate how components interact within a system.

Science and Engineering Practices:

Developing and Using Models
Constructing Explanations
Analyzing and Interpreting Data

Crosscutting Concepts:

Systems and System Models
Structure and Function
Cause and Effect

• Interpreting labeled diagrams
• Identifying function of components in a system
• Explaining multi-step cause-and-effect processes
• Connecting physical evidence to conceptual reasoning

Students practice analyzing technical diagrams and constructing structured explanations.

Day 1 – Deconstruction and Observation

Students wear safety glasses and dismantle old electronics.

They are instructed to observe:

Board layout
Traces
Component density
Variations in board regions

Students sketch the board and label observable structures without yet naming components.

Purpose:
Move from abstract diagrams to tangible systems.

DOK: 2 – Observe and describe structure.

Day 2 – Identifying Components

Teacher introduces formal names and functions for:

Resistors
Capacitors
Diodes
Integrated circuits
Processor

Students locate and label components on their boards.

They answer:

What might this component regulate?
Why would uncontrolled current damage a system?

Purpose:
Transition from observation to functional reasoning.

DOK: 3 – Connect structure to function.

Day 3 – Pathway Mapping

Students trace electrical pathways across the board.

They identify:

Power input region
Processing region
Output region

Students compare to simple circuits from Segment 3.

They recognize:

Boards are organized systems of controlled loops.

Purpose:
Bridge simple circuit logic to complex regulation systems.

DOK: 3 – Analyze system structure.

Day 4 – Component Function Deepening

Students complete structured analysis:

Resistor – limits current
Capacitor – stores and releases charge
Diode – controls direction
Processor – interprets signals

Students explain how these components:

Prevent damage
Stabilize voltage
Shape signals

Purpose:
Highlight regulation as prerequisite for digital processing.

DOK: 3

Optional Day 5 – System Explanation Writing

Students respond:

Explain how a circuit board differs from a simple circuit.
Describe how at least two components regulate electrical flow.

Purpose:
Prepare for binary and processing discussions.

DOK: 3

Students recognize:

Phones, game consoles, and laptops contain boards similar to what they dismantled.
Component failure explains device malfunction.
Engineering decisions shape device durability and cost.

This grounds digital technology in physical reality.

• The processor does all the work alone.
• Electricity flows randomly through boards.
• Components are decorative or redundant.
• More components always means better performance.
• Regulation is optional rather than necessary.

Teacher pushes students to articulate regulation as essential to system stability.

• Provide labeled component reference sheets.
• Offer guided pathway tracing worksheets.
• Allow collaborative identification.
• Provide structured explanation stems.
• Extension: Compare two boards and infer purpose differences.

Formative Assessments:

• Labeled circuit board diagram
• Component-function matching activity
• Written explanation of regulation

Exit Ticket Prompt:

Explain why a resistor is necessary in a circuit board.
What could happen if it were removed?

Evaluation Criteria:

Accurate identification of components
Clear explanation of function
Connection between regulation and system stability
Use of evidence from board observation