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Body Lab 3-5 / Week 07 / Body Lab Day
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Week 07 · Brain and Nerves

Body Lab Day

Body Lab Day: Ruler Drop
// The control center and its messengers
⏱ about 15 min

Body Lab Day: Ruler Drop

The family gathers at the kitchen table. Rocket holds the ruler and waits.

"Ready?" he asks. Then he drops it. Raven pinches it fast!

"Now, what do you notice about each try?" Raven asks.

Nova hovers above the data table. "Write every number down," she says. "Even the surprising ones."

Everyone gets a turn.

  1. The brain is the body's control center.
  2. The cerebrum thinks, the cerebellum balances, the brain stem runs automatic jobs.
  3. The spinal cord and nerves carry messages back and forth.
  4. A reflex is an automatic action.
  5. Practice builds pathways between neurons.
◇ RULER DROP CHALLENGE
One person holds the ruler at the high end. The zero end hangs at the bottom.
The catcher holds an open thumb and finger just around the zero end.
The holder lets go without warning. The catcher pinches it.
Read the number at the top of the catcher's fingers. Write it down.
Do three tries each. Then switch jobs.
Look at your numbers. Did practice change them?
Safety first
Use a plastic or wooden ruler with smooth edges. A grown-up checks it first.
Drop the ruler straight down, never toward anyone.
Joining in is a choice. Anyone can just be the ruler holder.
For a grown-up
This is a playful test, not a score. Everyone's numbers will be different, and that is fine.
Ask: what did you notice? Did tries get faster?
PlayerTry 1Try 2Try 3
Player A
Player B
BODY LAB CHECK
  • Read the question.
  • Tap your answer.
Which number shows the fastest catch?
Which body parts work together in the ruler drop?
Which part of the nervous system sits inside the backbone?
WHY THIS EXERCISEThe spinal cord runs inside the vertebrae of the backbone.

What a week, brain scientists! Next week we follow light into the eyes to learn how we see.

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