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Body Lab K-2 / Week 07 / Friday
5/6
Week 07 · Muscles and Moving

Friday

Engineer a better arm
// Muscles pull, and bones move
⏱ about 15 min

Friday: Engineer a better arm

Rocket made a paper arm with one string muscle.

It bends, but it will not straighten.

Raven asks, "What do you notice?"

Nova says, "What does a real arm have?"

Find the problem first

Engineers find the problem before they build.

They ask questions and look closely.

Rocket asks: why does my arm stay bent?

His arm has only one string muscle.

One string can only pull one way.

A real arm has a muscle pair.

You need

  • Two strips of stiff paper
  • One paper fastener
  • Two pieces of string
  • Tape
Safety first
A grown-up pokes the hole for the fastener.
Fastener points are sharp, so a grown-up bends them.
Keep small parts out of mouths.

Steps

  1. A grown-up joins the two strips with the fastener.
  2. Now the strips bend like an elbow.
  3. Tape one string along the top side.
  4. Pull it. Does the arm bend?
  5. Tape a second string along the bottom side.
  6. Pull the second string. Does the arm straighten?
DEFINE THE PROBLEM
  • Read the question.
  • Tap your answer.
What was wrong with Rocket’s first arm?
What did the arm need?
What do engineers do first?
ENGINEER STEPS
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last
SentenceTrue or false?
One string can pull the arm two ways.?
Rocket’s mistake helped him learn.?
Engineers ask questions about a problem.?
WHY THIS EXERCISEA clear problem leads to a better design.
Draw your paper arm with two string muscles.

Word Spot review

Let us review this week's sight words.

Look at each word. Say it. Spell it.

May: M-A-Y.

Of: O-F.

Old: O-L-D.

Men: M-E-N.

Need: N-E-E-D.

Land: L-A-N-D.

Different: D-I-F-F-E-R-E-N-T.

Home: H-O-M-E.

FIND THE WORD
  • Listen to the word.
  • Tap it.
Find the word you hear.
Find the word you hear.
Find the word you hear.
Find the word you hear.
FIND THE WORD
  • Listen to the word.
  • Tap it.
Find the word you hear.
Find the word you hear.
Find the word you hear.
Find the word you hear.
FILL THE GAP
  • Listen to the sentence.
  • Tap the missing word.
It ___ rain today.
I have a cup ___ water.
I found an ___ shell.
Two ___ fixed the road.

Hooray for Rocket’s mistake! It led to a better arm.

Tomorrow is Body Lab Day with your family.

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