These are colorful plastic sticks that snap together, but are still able to move freely to form different angles. Each color is a different length, which is written on the stick in both metric and U.S. Standard measurements. At my school, we use these in third through fifth grade. Not only do we use them when studying angles, but they are great for learning about polygons. We build different types of polygons, but also test out which lengths of Anglegs will snap together and why or why not, as well as what types of angles are formed within the polygons. You can find these under the names Anglegs or Geostix, but they’re both the same item.