Monday, January 26, 2015

The Arch & That Medieval Thing

As we investigated the field of archeology and learned about the science behind uncovering ancient ruins, 2nd, 3rd, and 4th graders became very interested in how buildings were constructed thousands of years ago. Our path led us to Rome and in particular, the longevity of the Roman arch bridge design. We briefly covered the history of bridges and students began to identify the basic types of bridges and to understand the forces of gravity, tension, and compression that act on them. Students formed human arches and felt the forces in action! After they tried creating model arches with small stones and a sand/corn starch mixture, many students decided that using a removable frame as a base was key to successfully constructing a model archway.

They found that building an arch is anything but easy. Since the arch is completely unstable until the two sides meet in the middle at the keystone, students realized why engineers for years used wooden forms on each side to hold the structure in place until the two spans met in the middle.

Others were interested in comparing different materials for constructing an arch and they tested arch design using sugar cubes and glue (but said they would rather use thick frosting next time, concluding that the mortar is a most important factor for success!)

In the Kindergarten and 1st grade classroom, our investigators developed a deep interest in castles, knights, and Medieval times. In December, students began noticing the different geometric shapes that can be found in castle architecture. In several classroom-wide hunts, they identified shapes that resembled certain attributes of a castle. We introduced 3D-shape vocabulary and played with handheld models. Students became comfortable counting the faces, vertices, and edges of geometric shapes.

January brought us to an investigation of simple machines as they relate to castles. We provided several materials challenges centered on levers and learned about force, effort, and load. Students tested different shapes that could be used as a fulcrum, and experimented with moving the placement of fulcrum along the arm. They each set up their own mini seesaw, using a 12-inch ruler (the arm), dixie cups (as load and effort containers), a thick marker (fulcrum) and proceeded to investigate how the effort changed depending on the position of the fulcrum from the load. Another time they used a large thick wood board for an arm and a thick cylinder piece for the fulcrum and were able to lift a box of books and a classmate!