The Stairs That Return
Investigate where an escalator’s steps go on the way back, how they stay level on the way up, why their tops are ridged like teeth, what a crowd does to the motor and how the whole machine stops. Use a working escalator to compare tracks, combs, handrails and brakes. Nine investigations for ages 12 and up.
Library
Shape a moving staircase
Lesson 1
The Half You Never See
Every step disappears under the floor at the top, and almost two thirds of them are out of sight at any moment.
StartLesson 2
A Stair That Refuses to Tilt
The steps climb a slope and flatten out at the top, and not one of them ever tips.
StartLesson 3
The Gap at the Edge
A floor turns into a staircase under your feet, and the crack between the steps never opens.
StartLesson 4
A Steady Turn, an Uneven Ride
The wheel turns perfectly steadily, and the chain it pulls still does not.
Start
Review and assessment
Lesson 10
Test: The Stairs That Return
Review the course ideas by applying them to new situations, with kind feedback after every answer.
Locked till you take the prior lesson