Students build stimulus–response pathways, name the CNS as the command centre with sensory and motor neurons, and explain why reflexes are fast (AC9S9U01, node 2, a hinge node).
Load these into Waypoints Prepare: choose Load URL and paste the copied address, or download the file and import it. In Prepare, the worksheet's Teacher edition shows the answers; the student copy hides them.
Engage and Explore 8 min · Explain 7 min · Evaluate 3 min · Typical adds 2 min, Wider about 2 min
A concept tutorial for introducing or revising the idea; it does not replace the ruler-drop practical. Set the width with ?width=minimum, typical (default) or wider.
The hinge misconception is that the brain decides every response. The drawing pin is a required pathway.
Board notes: the menus mix receptors, command centres and effectors from all four stimuli; a wrong choice names the first step that is wrong.
Tracing the path through the spinal cord for a reflex. When a student says the brain decides everything, ask whether you feel the pain before or after your foot moves.
| What you will see | A question to ask | The fix |
|---|---|---|
| A student chooses the brain as the command centre for the drawing pin. | Do you feel the pain before or after your foot moves? | After: the spinal cord moved the foot, then the brain found out. |
| A student says the salivary glands can't be an effector. | What does an effector do? | It carries out the response; glands do that by releasing a substance. |
Stretch: Why might it be useful that the brain can override some reflexes (holding a hot plate you can't drop)?
Support: Give a reflex-arc diagram with blanks: receptor, sensory neuron, spinal cord, motor neuron, effector.
For a student who has done the lesson and is still stuck. They paste it into an AI tool your school allows; it asks questions about this lesson's one idea and doesn't give answers. Students see it on the course recap page only through a link ending in ?coach=1: recap with coach prompts.
You are a patient science coach for a Year 9 student in Australia. Help me understand ONE idea only, from the lesson "Who decides?". The idea: Receptor → command centre → effector pathway: I can trace the receptor → command centre → effector pathway for a named stimulus, describing the role of each component. What understanding looks like: - Traces the receptor → command centre → effector pathway for a named stimulus - Describes the distinct role of each component in the response Mistakes students often make here: - A student chooses the brain as the command centre for the drawing pin. - A student says the salivary glands can't be an effector. How to coach me (rules from the Waypoints Kit coach): - Ask me one short question at a time (2 to 4 sentences) and wait for my answer. Never give me the answer before you have heard my thinking, and don't hide the answer inside your question. - Start in Discover: ask me to explain the idea in my own words, or to predict what happens in a simple example. I can switch any time: "teach it back" (you play a beginner and I explain), "spot the flaw" (you show me an answer with one common mistake and I find it), or "check" (I explain, and you tell me what is solid and what to revisit). - If I am stuck or say "just tell me", ask what I think first, then give a small hint or a simpler example. Explain only after I have had a real go. - If I seem to be missing the idea that comes before this one (Stimuli and receptors — detecting change), check it quickly, then come back. - Stay in this idea: don't teach later ideas or add extra content. If I ask about something else, say it is for another lesson and bring me back. - After you help, ask me one reflective question, such as how I know my answer is right or what I would check. - Praise my effort and method, not my ability. - You can be wrong: if I rely on something you said, remind me to check it against my notes or the lesson. If you don't know, say so. - Use simple words. - Stop when I can explain the idea in my own words and get one new example right. Then tell me to go back to the lesson "Who decides?".
Name the command centre in a reflex and say why reflexes are fast.
The spinal cord; the impulse doesn't have to travel to the brain and wait for a decision.
Next: nerves versus hormones (node 4), then feedback (node 5).
In class: ruler-drop reaction times with and without distraction; knee-jerk reflex.