Grade Level: 5th Grade
Air pressure, or atmospheric pressure, is the pressure of the atmosphere on objects. Barometers are typically used to measure atmospheric pressure. Made of a liquid filled glass tube, the level of liquid will rise when the pressure increases and fall when the pressure drops. Lower barometric pressure tends to be associated with precipitation and cloudiness, while higher readings are related to sunshine and calmer weather. Air is made of invisible particles. The density of these particles is affected by atmospheric pressure. The greater the pressure, the more densely packed the particles are. In comparison, less pressure means a lower density of air particles. While the particles are too small to be observed, the effects of the particles and changing their density are often visible.
Martinez, Elizabeth, "Physical Science - UNDER PRESSURE: Matter and its Interactions" (2019). Model NGSS Lessons: 4th - 5th Grade. 16.