Engineering

Egg Drop on a Budget

Protect one raw egg using materials that all cost points. Sketch and predict before you build, drop it three times, and score survival divided by what you spent.

Hard · 2 hours

Introduction

Anyone can protect an egg if they are allowed unlimited padding. Wrap it in a pillow and you are finished, and you have learned nothing.

So this version charges you. Every straw, every inch of tape, every cotton ball costs points, and your score is whether the egg survived divided by what you spent. Suddenly the design matters far more than the padding.

The Why

Real engineering almost never asks for the best possible thing. It asks for the best thing you can build within the money, the weight, or the space you were given, which is called designing under constraint. The budget is what turns this from a craft project into an engineering problem. Writing your prediction down before the drop is the other half: if you only decide what you expected after you have seen the result, you can talk yourself into believing you knew all along.

Step-by-Step Instructions

1
Agree on a drop height with an adult and use that exact height every round. A second-floor window or the top of a step ladder both work, as long as the landing zone below is clear.
2
Copy out the price list and set a budget for round one. Fifteen points is a good starting limit.
3
Sketch your design before you touch any materials. Label which part slows the fall, which part absorbs the impact, and which part holds the egg still.
4
Write your prediction: will the egg survive, and which part of your design will fail first? One sentence each, and no changing it afterward.
5
Build it, then add up what you actually spent. If you went over budget, take something off before you drop.
6
Drop it. Do not throw it downward, just let go. Open it up, photograph the damage, and write what actually happened next to what you predicted.
7
Run two more rounds, each on a smaller budget than the last. Score every round as survival divided by points spent, and see whether being poorer forced you to get smarter.

Drop Log

One row per round. The prediction column gets filled in before the drop, never after.

Round	Budget	Points spent	Predicted result	Actual result	Score
Row 1, Round	Row 1, Budget	Row 1, Points spent	Row 1, Predicted result	Row 1, Actual result	Row 1, Score
Row 2, Round	Row 2, Budget	Row 2, Points spent	Row 2, Predicted result	Row 2, Actual result	Row 2, Score
Row 3, Round	Row 3, Budget	Row 3, Points spent	Row 3, Predicted result	Row 3, Actual result	Row 3, Score

Score is 1 for a surviving egg and 0 for a broken one, divided by the points you spent. A cracked but unbroken egg counts as a half.

Materials List

One raw egg per attempt, plus a couple of spares
Drinking straws, 1 point each
Cotton balls, 3 points each
Paper, 1 point per sheet
Cardboard, 2 points per hand-sized piece
String, 1 point per arm length
Tape, 1 point per 10 cm
A plastic bag, 5 points
A ruler, a pencil, and paper for sketching, free
A tarp, trash bag, or old towel for the landing zone

Safety First!

An adult must set and approve both the drop height and the landing zone, and must be the one releasing the egg from any height above head level. Keep everyone clear of the landing area before each drop. Raw egg can carry salmonella, so work on a washable surface, wash your hands after every round, and clean up a broken egg right away.

Challenge Mode

Cut your budget in half and try to keep the egg alive anyway. Then try the opposite: keep the budget the same but double the drop height. Which limit was harder to design around? Most engineering problems have exactly this shape, and working out which constraint is the binding one is most of the skill.