Nerve Navigator

Teacher Facilitation Guide

Grade Level: 7th Grade

Subject: Life Science

Duration: 50 Minutes

Learning Objectives

Differentiate between the roles and locations of sensory neurons, interneurons, and motor neurons.
Trace the path of an electrical impulse through the nervous system during a stimulus-response event.

Materials Needed

Metric Rulers (1 per pair)
Signal Squad Student Worksheets
Impulse Odyssey Narrative Sheets
"Neural Speedsters" Slide Deck

Key Vocabulary

Sensory Neuron Interneuron Motor Neuron Stimulus Reaction Time

Lesson Flow

1

Warm-Up: The Ruler Drop (5 min)

Engage students in a physical demonstration of reaction time.

"Today we're testing how fast your brain can talk to your hands. Hold the ruler at the 30cm mark. Your partner puts their fingers at 0cm without touching. Drop it without warning! Record where they catch it."

2

Video & Guided Notes (10 min)

Watch "How the Brain Works." Focus on the 0:59-1:26 segment for definitions.

Pause at 0:17: Discuss "Input vs Output" in sports.

Pause at 1:26: Trace the signal from "Stepping on a Lego" to "Lifting the foot."

3

Main Activity: Impulse Odyssey (25 min)

Students write a 1st-person narrative of an electrical impulse.

Must start at a Sensory Neuron (the spark).
Must pass through the spinal cord/brain via Interneurons (the decision).
Must end at a Motor Neuron (the action).

4

Extension & Wrap-Up (10 min)

Discuss: Why did reaction times improve over 5 trials?

Key Concept: Neural pathways strengthen with repetition (Muscle Memory). The more a circuit is used, the more efficient the signal transfer becomes.

Facilitation Tips

• For the ruler drop, ensure students aren't "anticipating" by looking at their partner's hand instead of the ruler.
• Use the "Gift Box" metaphor from the video (1:14) to explain interneurons—they are the hand-off between sensing and acting.
• Challenge fast finishers to add a "Reflex" branch to their story where the signal skips the brain and only hits the spinal cord.

Nerve Navigator Teacher Guide

Nerve Navigator Teacher Guide