Gumdrop Engineering

Providing engaging and exploratory learning opportunities allow curious children to develop their creative and analytical skills. This simple building activity promotes creative thinking and innovative problem solving for children of various ages and interests.

Using colorful gumdrop candies (or marshmallows) and toothpicks, little engineers can develop fine motor skills while exploring color sorting and pattern making. More advanced builders can create simple 2D shapes and complex 3D geometric structures.

For this gumdrop building session, you’ll need typical 2 1/2″ long toothpicks, 4″ long mini-bamboo skewers, an multi-colored gumdrops. (I just set out the building materials as shown above and let them get right to work.)

First, allow young builders to explore the materials and experiment with building techniques. Little ones may just sort the gumdrops by color or create long chains. Older children may experiment with building intricate domes or tall towers.

To take Gumdrop Engineering a step further, the activities below use the same materials to explore basic structural concepts, specifically the importance of geometry in building.

The Strongest Geometry

Now that you have experimented with the materials, there are two important rules for building towers. First, a tall, skinny structure can fall over easily. Adding a wide and sturdy base makes it more stable. Second, even when using efficient, light-weight materials, a tower can buckle, or bend, under its own weight. Using strong, stiff shapes keeps a tower from breaking.

Activity #1: Triangle vs. Square

Using gumdrops (or marshmallows) and toothpicks, build both a simple square and triangle using the gumdrops as connectors. Attempt to shift or distort the square; attempt to distort the triangle. Which shape is stronger? Now build a pyramid and a cube using the same technique. Attempt to distort both forms. Which is is stronger and holds its original shape?

Triangles are the strongest shape because they have fixed angles so they do not distort or shift easily. To design and build a stable, tall building that resists compressive, tensile, and shear forces, the right geometry is required. This typically means that triangles can be found throughout the building’s structural design. These triangles are formed using braced rectangles and trusses. Nearly all skyscrapers use one or both of these types of structural geometry.

Activity #2: Framing for Shear Forces

As in Activity #1, build a simple square using toothpicks using a gumdrop to connect each corner. Push the frame to distort the square into a parallelogram. Re-align the square. Now, insert the 4″ wood skewer diagonally across the square and insert ends into the gumdrops. This is a braced rectangle. Attempt to distort the shape. Add a second diagonal skewer making an “x” across the center of the square. Attempt to distort again. Notice how these diagonal “beams” support the sides of the square and make this a much stronger shape. Likewise, adding diagonal bracing to a cube makes this geometry more stable. A truss is created when several of these braced rectangles are aligned. Three braced squares can form a very strong structure called a triangular prism.

Activity #3: Skyscraper Architects

Now using these geometry principles, build a structure. Do you recall what are the two important rules to follow when constructing a tall and stable tower? What geometric shape must be created to ensure the strongest structure?

And of course, who can build the tallest tower?