Systems, Order, and Organization
The natural and designed world is complex; it is too large and complicated to investigate and comprehend all at once. Scientists and students learn to define small portions for the convenience of investigation. The units of investigation can be referred to as "systems." A system is an organized group of related objects or components that form a whole. Systems can consist, for example, of organisms, machines, fundamental particles, galaxies, ideas, numbers, transportation, and education. Systems have boundaries, components, resources flow (input and output), and feedback.
- The energy system is highly complex, spanning the geologic processes in which coal is produced deep in the earth to the efficiency with which lumens are produced in a light bulb. Energized Learning focuses on a subset of this entire systemthe homeand provides a sophisticated simulation tool allowing students to analyze the dynamics of residential energy use. The exercise entitled Energy Services A Central Concept on p. 20 of our report provides a conceptual foundation for the systems perspective on the nature and value of energy for society in general, and the relationship between raw energy and the ultimate services provided in particular.
The goal of this standard is to think and analyze in terms of systems. Thinking and analyzing in terms of systems will help students keep track of mass, energy, objects, organisms, and events referred to in the other content standards. The idea of simple systems encompasses subsystems as well as identifying the structure and function of systems, feedback and equilibrium, and the distinction between open and closed systems.
- The Unit Conversions exercise helps students build competence in converting among an array of energy units, and keeping track of their results in ways that enable meaningful comparisons among different forms of energy.
Prediction is the use of knowledge to identify and explain observations, or changes, in advance. The use of mathematics, especially probability, allows for greater or lesser certainty of predictions. [See Program Standard C]
- Energized Learnings residential energy simulation modelThe Home Energy Saverallows students to make informed predictions of a homes energy use, with its existing technologies as well as with changes to more energy-efficient ones.
Order--the behavior of units of matter, objects, organisms, or events in the universe--can be described statistically. Probability is the relative certainty (or uncertainty) that individuals can assign to selected events happening (or not happening) in a specified space or time. In science, reduction of uncertainty occurs through such processes as the development of knowledge about factors influencing objects, organisms, systems, or events; better and more observations; and better explanatory models.
- The statistical exercises in the Bringing it Home exercise introduce students to different ways of normalizing energy use (e.g. energy per unit of home floor area or per occupant) in an attempt to explain differences in usage from one home to another. The spreadsheet tool accompanying the "Getting Started" lesson engages the students in applying basic statistical tools (Standard Deviation and Coefficient of Variation) to a dataset of results from all students in the class.
Evidence, Models, and Explanation
Evidence consists of observations and data on which to base scientific explanations. Using evidence to understand interactions allows individuals to predict changes in natural and designed systems. [See Content Standard A (all grade levels) [K-4] [5-8] [9-12]]
- Energized Learnings underlying heating and cooling simulator accounts for complex thermodynamic processes within a building. Students can also use the tool to evaluate critical interactions between measures. For example, the total energy savings for a set of, say, 10 measures will almost be less than the sum of each measures savings taken individually. This observation can form the basis of interesting classroom discussion.
Models are tentative schemes or structures that correspond to real objects, events, or classes of events, and that have explanatory power. Models help scientists and engineers understand how things work. Models take many forms, including physical objects, plans, mental constructs, mathematical equations, and computer simulations.
- Energized Learning relies heavily on student-run models. However, it also emphasizes that models have limitations and are only an approximate description of reality. Students are encouraged to think critically about their results. Having students compare their actual energy bills to the model results is one method for stimulating this type of discussion.
Return to top
Return to Teacher Resources