Alpha science classroom：Popsicle Stick Trusses

Do children observe a bridge, or see a building under construction, and notice the large metal support beams? What about all the wooden beams in a house under construction? Did you notice that sometimes these beams form different geometric shapes, such as triangles or squares? And do kids know which shapes are the most stable? Today, the alpha science classroom produced Popsicle Stick Trusses and in this children's physical science experiments project we were able to discover which shapes are the most stable. Also in this kid's science experiments activity, children will become structural engineers and invent their own strongest structure.

Alpha science classroom：Popsicle Stick Trusses，Materials

• Popsicle sticks (at least 7)

• Small binder clips (at least 7)

Alpha Science Classroom: Popsicle Stick Truss, Making Steps

Step 1: First, children use binder clips to attach two popsicle sticks end to end, securing one end of each popsicle stick to one end.

Step 2: The kids gently twist them back and forth, spinning around the joint where they are attached by the binder clips (note: do this by sliding the flats of the popsicle sticks, don't try to "break" them by bending them). How easy is it to rotate a popsicle stick around a joint?

Step 3: Now, the kids make a square out of popsicle sticks that are connected with binder clips at the four corners.

Step 4: Children hold two adjacent popsicle sticks with their fingers and gently try to rotate them relative to the joint that connects them. How easy is it to spin a popsicle stick? What happens to the shape of the entire square?

Step 5: Children hold two opposing popsicles and gently try to slide back and forth in parallel. How easy is it to slide a popsicle stick back and forth? What happens to the shape of the entire square?

Step 6: Now, the kids make a triangle with the three corners of the popsicle stick connected with binder clips.

Step 7: Hold two adjacent popsicle sticks between your fingers and try to rotate them as you did with the square. what happened? Can you rotate the popsicle stick, or does the triangle keep its shape?

Alpha Science Classroom: Popsicle Stick Truss, The Science

alpha science classroom believes that children should have discovered that it is very easy to rotate the popsicle sticks in a square truss. When you rotate two adjacent popsicle sticks or slide two opposing sticks, the sticks stay connected, but the entire square is deformed to form a parallelogram.

However, when you try to rotate the popsicle sticks in the triangular truss, they do not move. The triangle design is more "robust" - the popsicle sticks are arranged in such a way that when you push or pull them, they don't rotate.

This happens because of something engineers call "degrees of freedom. A square truss has one degree of freedom, which means that it can move in one direction (in this case, one direction of rotation - it can rotate from a square to a parallelogram). The only way to prevent a square from rotating is to pinch the joint very, very hard (imagine using a stronger flipchart). You can probably imagine why it is undesirable to use only squares when building structures - all the joints have to be super strong! Triangles, however, have a zero point. However, the triangle has zero degrees of freedom - all of its popsicle sticks are fixed there and cannot be rotated. This means you can build a truss structure out of triangles that won't rotate or deform, even though the joints are just gently held together with flip clips.

I believe that the children have made the most solid shape, then the children's physical science experiments activity, then the success. At the same time, children can also learn the real mystery of engineering structural and physics through the kid's science experiments project, and become the greatest architects in the future, casting their own homes.

alpha science toys create many interesting physical science experiment kits for children to enjoy the magic of science and to accomplish their own scientific dreams.