Surrounding fluids exert equal pushes all around an object.


Air pressure has no up or down influence (neutral).


Liquid presses equally from all sides regardless of depth.


Whichever surface has the greater amount of fluid above or below the object has the greater push by the fluid on the surface.


Fluid mediums exert an upward push only.


Air pressure is a big up influence (only direction).


Liquid presses up only.


Fluids exert bigger up forces on lighter objects.


Surrounding fluid mediums exert a net downward push.


Air pressure is a down influence (only direction).


Liquid presses (net press) down.


Weight of an object is directly proportional to medium pressure on it.


Weight is proportional to air pressure.


Weight is proportional to liquid pressure.


SOURCE: Minstrell (2000, p. 52).

For example, to assess student learning as part of a seventh-grade unit called the Antarctica Project, students work in groups to design a research station for scientists. Self- and peer-assessment strategies are used. Students are asked to continually consider and discuss four general questions while they work on classroom projects: What are we learning? What is quality work? To whom do we hold ourselves accountable? and How do we use assessment tools to learn more? Assessment activities include journal writing, group design of scoring rubrics (or criteria), and group presentations followed by peer critiques based on the rubrics. The group conversations that define the rubric, together with peer and self-evaluation of how a particular piece of work fares against that rubric, create a shared vocabulary and standards for quality work (Cole, Coffey, and Goldman, 1999).

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