DI Parkview Destination Imagination

LESSON 02 · OCTOBER · ANY AGE

Balancing Act

Stack it, load it, hold it up. Find the one invisible point everything balances on, then build a paper tower strong enough to carry a book.

Play the game → The Paper Tower build

THE BIG IDEA

Everything balances on one point. Keep that point over whatever is holding it up, and it stands. Let it drift past the edge, and it falls.

That point is the center of mass. The second half of the lesson is about strength: a flat sheet of paper can't hold up a pencil, but the same sheet rolled into a tube can hold up a book. Engineers get strength from shape, not just from more stuff.

SIX BALANCE IDEAS

What keeps it up. What knocks it down.

balanced!

01 · Center of Mass

Find the Balance Point

Every object acts like all its weight is squished into one spot. Hold it right under that spot and it won't tip. For a hammer, that spot is way over by the heavy head, not in the middle.

In the game
The green dot
In real life
A seesaw, a tightrope walker's long pole, a backpack
Science word
Center of mass (center of gravity)
past the edge!

02 · Base of Support

Stay Over the Edge

Whatever holds something up is its base. While the balance point is over the base, a tip rocks back. Once it passes the edge, it falls. A wider base gives more room to wobble.

In the game
The tray in his hands
In real life
Feet apart on a moving bus, a traffic cone, a camera tripod
Science word
Base of support, stability
HEAVY LOW HEAVY HIGH

03 · Low Center of Mass

Heavy Goes Low

Same blocks, same bump. Heavy on the bottom keeps the balance point low, so a bump barely moves it. Heavy on top swings it way out past the edge.

In the game
Anvil and clock early, pizza boxes up high
In real life
Loading a truck or a ship, race cars built low to the road
Science word
Low center of gravity
evened out

04 · Lopsided Loads

Even Out the Load

Some things carry their weight at one end. Set them down off-center, or balance them with weight on the other side, and the load evens out.

In the game
Hammer, guitar, rubber chicken
In real life
A crane's counterweight, carrying two grocery bags instead of one
Science word
Counterweight, torque
FLAT FOLDED

05 · Structures

Shape Beats Material

A flat sheet sags under almost nothing. Fold it, roll it or crease it and the same sheet holds a book. That's why cardboard is corrugated and bridges use triangles.

In the game
The Paper Tower build
In real life
Corrugated cardboard, steel I-beams, bridge trusses
Science word
Columns, corrugation, strength-to-weight
too late… too far…

06 · Feedback

Reacting Too Late

Balance a broom on your hand: you always move a moment late, so you overshoot and it wobbles back and forth. The guy in the game does the same, and the heavier and taller the stack, the bigger his overshoots.

In the game
His wobble
In real life
Balancing a broom, riding a bike slowly, a self-balancing scooter
Science word
Feedback, reaction time

HANDS-ON · THE PAPER TOWER

Tallest tower that holds a book.

Each team gets

  • 10 sheets of printer paper
  • 1 meter of masking tape
  • Scissors

Rules

  • 20 minutes to build. The tower has to stand on its own, with no taping it to the table.
  • Test: set one hardcover book flat on top. It has to hold for 10 seconds.
  • Score: the height from the table to the bottom of the book, in centimeters. If it doesn't hold, fix it and test again before time's up.

Engineering bonus round

Keep adding books, one at a time, until the tower fails. Watch how it fails:

  • It tipped over? That's a balance problem. The load's center of mass went past the base. Widen the base or center the load.
  • It crushed or bent? That's a strength problem. The columns were too thin or too flat. Roll them tighter or use more of them.

Knowing which one happened is the whole lesson. The game teaches the first one; the tower teaches both.

PICK YOUR AGE

Same lesson, four levels.

Every age stacks and every age builds a tower. The words, the rules and the math grow with them.

Make it stand.

Words to use

balancewobbleheavylightwide

Build it

4 sheets of paper, as much tape as they want. Build a tower that holds a paperback book. Grown-ups can tear tape; kids do all the rolling and folding.

Play it

Play together: the kid picks each item, a grown-up helps aim.

Ask, don't tell

  • Which way is it going to fall?
  • Where is the heavy part?
  • Why did the wide one stay up?

Stretch

Stack 5 blocks as high as you can. Then try the heaviest block on the bottom and do it again.

Find the balance point.

Words to use

center of massbasestablecounterweight

Build it

10 sheets, 60 cm of tape. The tower must hold a hardcover book for 10 seconds. Try one team with rolled tubes and one with folded strips, then compare.

Play it

Play and watch the green dot. Before each drop, say out loud where the dot will move.

Ask, don't tell

  • Where is the balance point of a hammer? Test it on one finger.
  • Why do rolled tubes hold more than flat paper?
  • What should go on the bottom of the stack in the game?

Stretch

Find the balance point of 5 odd objects on one finger: a spoon, a shoe, a ruler with a coin taped to one end.

Build strong, stack smart.

Words to use

center of massbase of supporttorquecolumnload

Build it

The full Paper Tower rules, then the bonus round: add books until it fails and decide whether it tipped (balance) or crushed (strength).

Play it

Balancing Act all month. Plan two or three items ahead instead of one.

Ask, don't tell

  • Which failed first, the paper or the balance? How can you tell?
  • How does a wider base change what you can stack?
  • Why does the hammer balance so far from its middle?

Stretch

Roll single sheets into tubes 2 cm, 4 cm and 8 cm across. Stand each one up and load books. Which tube wins, and why?

Engineer it.

Words to use

center of mass = Σmx ÷ Σmtorque = force × distancebucklingstrength-to-weight

Build it

Paper Tower rules, scored like an engineer: (books held × height in cm) ÷ sheets used. Sketch how the load travels down through the tower to the table.

Play it

Balancing Act, then explain your strategy using center of mass and base of support. Top score teaches it to the younger kids.

Ask, don't tell

  • Find the hammer's center of mass: a 1 kg handle centered at 0 cm and a 7 kg head at 55 cm. (Answer: about 48 cm from the handle's middle.)
  • Why do tall, thin columns bend sideways (buckle) long before the paper crushes?
  • The game's guy reacts late. What would a faster reaction do to his wobble?

Stretch

Build a paper-and-ruler crane with a counterweight that holds a cup of coins 30 cm out without tipping.

RUN OF SHOW · ABOUT 60 MINUTES

The meeting.

  1. 0:00
    Hook (5 min). Balance a hammer (or a big spoon) on one finger. Ask: why won't it balance in the middle?
  2. 0:05
    The six balance ideas (8 min). Walk through the animations above. Demo: tape a coin to one end of a ruler and find the new balance point.
  3. 0:13
    Paper Tower (25 min). 20 minutes to build, then everyone tests with the book. Measure and write down each height. Older kids run the bonus round.
  4. 0:38
    Game lab (12 min). Pairs on laptops at parkviewdi.com/lab/stack. One kid picks, the other aims, then swap.
  5. 0:50
    Launch the challenge (8 min). Show the Balancing Act leaderboard. Everyone gets the same items in the same order this month, so it's fair.
  6. 0:58
    Exit question (2 min). Name one thing at home that's built with its heavy part low.

DI tie-in: DI's engineering challenges often ask teams to build a structure that holds weight. This is that skill in miniature. Let the kids decide every fold; coaches ask questions.

MATERIALS

Mostly paper.

  • Printer paper, 10 sheets per team
  • Masking tape, 1 meter per team
  • Scissors
  • A ruler or tape measure
  • 3–5 hardcover books, all about the same size
  • A hammer or big spoon (hook demo)
  • A ruler, a few coins, tape (balance point demo)
  • Laptops or Chromebooks for the game

THIS MONTH'S CHALLENGE · ALL AGES

★ Balancing Act

Stack the tallest pile you can on his tray. Each turn, pick 1 of 3 wacky items. Everyone gets the same choices in the same order this month, so it comes down to your decisions.

score = tallest settled stack, in meters

  • Anything that falls off = crash. Your best settled height is your score.
  • Submit with your first name, last initial and grade. One spot per kid, and a taller stack replaces your old one.
  • Anyone can replay any stack, so every height can be checked.
  • Each grade group's winner shows their strategy at the next meeting.

Tallest stacks by grade group

  1. No K–2 stacks yet. Be first!
  1. No Grades 3–5 stacks yet. Be first!
  1. No Grades 6–8 stacks yet. Be first!
  1. No Grades 9–12 stacks yet. Be first!
Start stacking →