How do climbers stick to the wall?
A plain-English answer for grown-ups of kids aged 6–9, taken from the Yufena lesson that explores this question.
This is a members' lesson. Four other lessons are free to try.
The answer, for parents
Short answer: Sticky rubber makes friction, chalk soaks up sweat, and hips close to the wall keep a climber balanced.
Climbers wear shoes with soft, sticky rubber soles. The rubber squeezes into tiny bumps on the hold. This makes friction. Friction is a rubbing grip that stops sliding. Climbing makes hands sweaty. Sweat makes holds slippery. So climbers dip their hands in chalk. Chalk soaks up the sweat, and hands can grip better.
Gravity pulls everything down, even you. Keep your hips close to the wall. Then your weight sits over your feet, and you keep your balance. Climbers keep three hands and feet on the wall. They move just one at a time. This is called three points of contact. Strong legs push the body up, and arms help with balance.
In the lesson, your child puts this cause-and-effect chain in order: Rubber shoes squeeze into bumps → Friction stops feet sliding → Hips stay close to the wall → Legs push the body up → The climber reaches the top.
What if the climber slips? The rope catches them. A grown-up called a belayer holds the other end. The rope stretches a little, so the stop is gentle.
What if the wall is wet? Water makes holds slippery. There is less friction, so it is much harder to grip.
Try it with your child
Let's feel how weight pulls. Put on a backpack with a few heavy books. Lean on a wall with both hands, feet a little back. Count to ten. How do your arms feel? Now take the backpack off. Lean on the wall again. Is it easier? The heavy weight was pulling you away from the wall. Climbers keep their weight close.
Safety: Safety first: ask a grown-up to check the backpack is not too heavy. Lean only a little.
Explore it together in the full lesson
Guess, find clues, build the chain and try the experiment. Read it together.