Draft: this lesson was written with AI help and has not yet been read by a human editor.
1 What your class asks
This lesson asks you to find structures made to carry a load, to name the materials they are made of, and to say which properties of a material help it do its job. The museum offers one building element; the class looks at structures near school and home. 1
Curriculum expectations, with their official codes
- D2.2 identify structures that are objects designed to support a load, including those acting as supporting frameworks for objects
- D2.3 identify materials that are used to make various everyday objects, including structures
- D2.6 identify properties of materials that enable the objects made from them to perform their intended function
2 The lesson
What is holding this up?
Pick a roof, a bridge or a shelf and trace the path from the thing it carries down to the ground. Ask what each material along the way must be able to do.
Go deeper
Picture a big dome in Cairo. At al-Azhar, the dome rests on keel arches over old columns, and wooden beams brace the columns 2. A keel arch is a pointed arch shaped like an upturned boat 2 3. The historian Richard Yeomans says this is much lighter than the solid brick piers of an earlier building 2.
Think about it
Yeomans says the arches and wooden beams are much lighter than solid brick piers. If you were building a roof that must stay up, which would you choose, and why?
Into the museum
- Keel arch: the arch shaped like an upturned boat, and where it appears in Cairo's buildings.
- al-Azhar: the building whose dome rests on keel arches.
- al-Aqmar mosque: a front with three keel-arched niches.
Try this
Build a small arch or bridge from blocks or paper and load it with a book. Compare how it carries the load with the keel arch on this page.
3 Check yourself
Nothing here is marked or sent anywhere. It is for you.
In your own words: what does Keel arch have to do with this lesson?
Compare with the card
An arch shaped like an upturned boat. In the dome of al-Azhar in Cairo, the dome rests on pointed arches shaped like an upturned boat, standing on old columns held in place by wooden bars. Richard Yeomans describes this as much lighter than the solid brick piers of earlier building. What holds up the roof of a building you know?
I can now