A triangle is a three-sided polygon with interior angles totaling 180 degrees. A triangle can be split into four equal parts by taking a few measurements. The Sierpinski Triangle is an example of splitting triangles into fourths. In the Sierpinski Triangle, the process is repeated over and over to create smaller and smaller triangles within the original triangle.

Measure the length of each side of the triangle with a ruler. Write down each length, noting which measurement is for which side of the triangle.

Divide each measurement by 2 to find the midpoint of each side of the triangle.

Use the ruler and mark the midpoints on each side of the triangle.

Connect the midpoints using a straightedge and pencil. Draw a line from the midpoint of the bottom of the triangle to the midpoints of the other two sides, then connect the midpoints of those two sides. This creates four congruent triangles, meaning that all are the same size and have the same angles.