This week our 2nd and 3rd graders learned about what materials are used to build dams. Beavers use logs and sticks and even mud (Check out the video here: https://www.youtube.com/watch?v=yJjaQExOPPY ). Humans use concrete and other materials. In STREAM, students were given a variety of materials to choose from to build their dams, and the dams were tested to see if they could hold back water. If the water broke through, the students had to re-engineer the dams. In some cases, it took the students up to 5 or 6 times to redesign their dams until they could hold back water. See some pictures of students testing their dams.