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Builder's Lab / Week 04 / Wednesday
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Week 04 · Bridge the Gap

Wednesday

Build bridge version 1
// A paper bridge that holds the most coins
⏱ about 20 min

Wednesday: Build Bridge Version 1

Rocket lays a flat sheet across the gap.

"A bridge! Easy!" Rocket says.

Raven hands Rocket the coin cup. "Let us test it."

Nova shines a light on the middle. "Coins go right here."

Rocket sets down the first coin.

You need

  • Books, to make two stacks the same height
  • One sheet of paper
  • A ruler
  • A pile of coins, all the same kind
Safety first
Coins can be a choking danger for little ones. Keep them away from babies.
Coins never go in your mouth.
Keep book stacks low and steady.

Build it

  1. Make two book stacks the same height.
  2. Use the ruler to set them 6 inches apart.
  3. Lay your bridge across the gap.
  4. Add coins to the middle, one at a time.
  5. Stop when it touches the table. Count the coins.
VersionShapeCoins held
Version 1
TEST IT RIGHT
  • Read the question.
  • Tap your answer.
Where do the coins go?
When do you stop adding coins?
SAME KIND OF COINS
  • Read the question.
  • Tap your answer.
Why use all the same kind of coin?

Why the middle?

The ends of the bridge rest on the books.

The middle has nothing under it.

So the middle is the hardest spot to hold up.

That makes it the best spot to test.

SET UP CHECK
  • Read the question.
  • Tap your answer.
The two book stacks must be what?
How far apart are the stacks?
Why test in the middle?
SafetyTrue or false?
Coins can go in your mouth.?
Keep coins away from babies.?
Tall, wobbly book stacks are safe.?
Use coins that are all the same kind.?
WHY THIS EXERCISESafe builders keep everyone in the house safe.
TEST THE BRIDGE
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last
Try it
Lay a flat sheet across your gap.
Add coins to the middle, one at a time.
Write the number in your table.

Version 1 is tested. Good counting!

Tomorrow, we see what happened.

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