Select Page

Roman Arch

  1. Home
  2. Knowledge Base
  3. Sensorial
  4. Visual Discrimination
  5. Roman Arch


Pictures of Roman Arches, ancient, modern, and local.  
Wooden base for building the arch. Support, lever, semicircular block.  
Basket with 9 trapezoidal prims, 1 small square prism, 2 small rectangular prisms, 17 large rectangular prisms, 2 small irregular trapezoidal prisms, 2 medium irregular trapezoidal prisms, 2 large irregular trapezoidal prisms. 


  1. Sitting with the child at a table, look at pictures of arches. Some ancient, monumental, and local. 
  2. Notice that the stones are not falling, but are being held up somehow. 
  3. Put the pictures away and place the arch materials on the table.  
  4. Remove the pieces from the basket and organize them by shape. 
  5. After organizing, place the arch base on the table. 
  6. Place the support block in the center of the board.
  7. Slide the lever into the support, raising the semicircle.  
  8. Begin to construct the arch by placing one trapezoidal prism on each side of the semicircular block. 
  9. Place the trapezoidal prisms on the semicircular block, alternating between left and right until there is a gap for one more block. 
  10. Dramatize the gap and the last trapezoidal prism.  
  11. After carefully placing the trapezoidal prism in the space, place one irregular prism on the left and another on the right, touching the trapezoidal prism of the arch. 
  12. On top of the irregular prisms and touching the walls, place one of the small matching rectangular prisms on each side.  
  13. Place the elongated irregular prisms next to the smaller rectangular prisms.  
  14. On the next level, place a rectangular prism on the outside of each side. 
  15. Place the irregular trapezoidal prisms on each side of the rectangular prisms.  
  16. Place the one small square prism in the gap between the irregular trapezoidal prisms. 
  17. Place a rectangular prism in the middle of the top layer. 
  18. Place a total of 5 rectangular prisms on the top layer, alternating from left to right. 
  19. On the next level, place 4 rectangular prisms in brick layer styles. 
  20. Continue until finished. 
  21. Hold the support block with the subdominant hand, and slowly pull the lever out. Watch the semicircle fall. 
  22. Place the lever on the table. 
  23. Remove the support and place it on the table.  
  24. Admire and examine the arch.  
  25. Place the lever in the support block. 
  26. Place the support near the edge of the board, pull the lever back to slightly drop the semicircle. 
  27. Slide the support under the arch. 
  28. Push the lever in to lift the semicircle and the arch with it. 
  29. Remove the pieces one at a time, top to bottom, and place them on the table randomly. 
  30. Invite the child to do it. 


Exercise 1: Presentation

The child builds the Roman arch as presented.

Exercise 2: Building the Arch Blindfolded

The child performs the exercise just as before, but this time he wears a blindfold, making it so that he has to use only his stereognostic senses to build the arch.


Telling the child the name of the structure is “Roman arch” and telling him the name of the “key stone.”

Control of Error

Visual, and built into the material as it won’t stand if not done properly.

Direct Purpose

To build the arch.

Indirect Purpose

Preparation for physics, gravity, and force.
Preparation for history.
Appreciation for monumental construction.
Functional geometry.


4 1/2 to 6


We show the child how to build the arch, we do not tell them how. 
Exploring, the child discovers how the prisms become load bearing, showing the function of the keystone. 

Was this article helpful?