Always change, at a constant rate in a constant direction. Equilibrium, or the ability of an object to return to its starting point, reliably, after an outside force has been applied. Identifying properties of matter. The sun stabilizes the solar system. Rocks stabilize the ground matter.
Rotation stabilizes the weather.
In this age, as no previous, society's concerns are science's concerns. Every scientist must seek to understand the ramifications of the research going on and its impact on the earth's citizens. At each grade level, issues that can be understood and acted on by the student, are addressed. Potential solutions are presented to impart a sense of challenge, rather than doom. When a distinguished, but elderly, scientist states that something is possible, he is almost certainly right.