Science Assessment ~ Ideas ~ Motion energy (kinetic energy) is associated with the speed and the mass of an object.

Key Idea: Unless prevented from doing so, energy will become uniformly distributed.

Sub-Ideas
Items & Student Performance
Misconceptions
NGSS

Students should know that:

Unless prevented from doing so, energy will become uniformly distributed among the atoms/molecules within a system or between the system and the surrounding environment.
When energy becomes uniformly distributed, the amount of energy present has not changed but the energy becomes less useful and less concentrated.
After a given amount of energy had become uniformly distributed, it takes additional energy to concentrate the diffuse energy and make it useful again.
Thermal energy in the surrounding environment is sometimes considered a less useful type of energy.

Boundaries:

Items do not ask students to perform any calculations. For example, students are not asked to use equations like KE = 1/2mv² or PE = mgh.
Items do not assess students’ understanding of entropy or the relationship between energy and entropy.

Percent of students answering correctly (click on the item ID number to view the item and additional data)
Item ID Number	Knowledge Being Assessed	Grades 4–5	Grades 6–8	Grades 9–12
RG162002	When a wind-up toy car is wound up and then let go, energy is concentrated as the spring is wound up and then becomes less concentrated as energy is transferred to the surrounding environment.	N/A	43%	55%
RG078003	Each time a person used a flashlight some of the energy from the battery was transferred to the surrounding environment. Eventually all of the energy became uniformly distributed in the surrounding environment and was no longer available to make the flashlight work.	N/A	32%	39%
RG067002	Saying that energy is used up when a machine operates means that some energy spread out to the surrounding environment as thermal energy, and that energy is now in a less useful form.	28%	29%	41%
RG145002	A device cannot power itself because some energy will be transferred to the surrounding environment, and that energy will no longer be available to be used by the device.	18%	21%	33%

Frequency of selecting a misconception
Misconception ID Number	Student Misconception	Grades 4–5	Grades 6–8	Grades 9–12
RGM005	Energy does not degrade (Trumper). It can be recycled through an ecosystem many times.	N/A	33%	26%
RGM010	Energy can be changed completely from one form to another (no energy losses) (Hapkiewicz, 1992).	33%	30%	23%
RGM007	Energy degradation means that the energy has been transferred someplace else so you can no longer use it (Pinto, et al., 2005).	29%	24%	25%
NGM060	Energy can be destroyed (Kruger, 1990; Trumper, 1998).	16%	26%	21%

Frequency of selecting a misconception was calculated by dividing the total number of times a misconception was chosen by the number of times it could have been chosen, averaged over the number of students answering the questions within this particular idea.

NGSS Statements
Code	Statement
PS3.D HS	Although energy cannot be destroyed, it can be converted to less useful forms--for example, to thermal energy in the surrounding environment.
PS3.B HS	Uncontrolled systems always evolve toward more stable states--that is, toward more uniform energy distribution (e.g., water flows downhill, objects hotter than their surrounding environment cool down).