Information is sent and received over physical or wireless paths. It is broken down into smaller pieces called packets, which are sent independently and reassembled at the destination. Students demonstrate their understanding of this flow of information by, for instance, drawing a model of the way packets are transmitted, programming an animation to show how packets are transmitted, or demonstrating this through an unplugged activity in which they physically act this out. For example, students could design a structure using building blocks or other materials with the intention of re-engineering it in another location, just as early Americans did after the intercontinental railroad was constructed in the 1850s (HSS.4.4.1, 4.4.2). Students could deconstruct the designed structure, place materials into specific containers (or plastic bags/brown paper bags/etc.), and develop instructions on how to recreate the structure once each container arrives at its intended destination. (CA NGSS: 3-5-ETS1) For example, students could cut up a map of the United States by state lines. Students could then place the states in envelopes and transmit the "packets" through a physical network, represented by multiple students spreading out in arms reach of at least two others. At the destination, the student who receives the packets resassembles the individual states back into a map of the United States. (HSS 5.9) Alternatively, students could perform a similar activity with a diatonic scale, cutting the scale into individual notes. Each note, in order, should be placed into a numbered envelope based on its location on the scale. These envelopes can be transmitted across the network of students and reassembled at the destination. (VAPA Music 4.1.2)