Drawings of energy: Evidence of the Next Generation Science Standards model of energy in diagrams

The Next Generation Science Standards (NGSS) provide a succession of objectives for energy learning and set an expectation for teachers to assess learners’ representations of energy in a variety of science contexts. To support teachers in evaluating the extent to which representations of energy display NGSS objectives, we have (i) discerned the constituent ideas that comprise the NGSS model of energy in the physical sciences and (ii) developed a checklist for assessing the extent to which an energy diagram provides evidence of the NGSS energy model. This energy diagram checklist is representation independent (so that diverse diagrams in a course may all be evaluated) and scenario independent (so that it can be applied throughout the physical science curriculum). We demonstrate the use of the checklist for assessing both pedagogical energy diagrams and learner-invented energy diagrams, including measuring a class’s increased facility with energy diagrams.

Figure 1

Top view of ring slider scenario, in which a metal ring is smacked by a bent-back ruler and slides across the floor.

Figure 2

Energy bar charts for ring slider scenario. While the ruler is pulled back (before it smacks the ring), all of the energy is potential energy. While the ring is sliding, the energy is partly kinetic (the ring is moving) and partly thermal (the ring and floor warm as they rub together).

Figure 3

Energy flow diagram for any continuously operating reversible device generating work from heat.

Figure 4

Energy tracking diagram for ring slider scenario. $E$, $K$, and $T$ represent elastic, kinetic, and thermal energy. Black, gray, and white arrows represent elastic expansion, mechanical work, and dissipation.

Figure 5

A learner-invented “energy picture” diagram for a wind turbine scenario.

Figure 6

A learner-invented “energy trajectory” diagram for a ring slider scenario.

Figure 7

A learner-invented “energy source and receiver” diagram for a spring compression scenario.

Figure 8

A learner-invented “energy snapshots” diagram for a wind turbine scenario.

Figure 9

A learner-invented “energy tracking snapshots” diagram for a wind turbine scenario.

Figure 10

A learner-invented “energy branching” diagram for a single-bulb circuit scenario.