The purpose of this resource is to measure the amounts of nitrogen, phosphorous and potassium in each horizon in a soil profile. Using a NPK test kit, students mix a dry, sieved soil sample into a solution and chemically extract the N, P, and K as nitrate, phosphate, and potassium. The N, P, and K amounts in the sample are determined by comparing the solution to a color chart. Students describe the ... Full description.

The purpose of this activity is to measure air pressure. Students record atmospheric pressure using a barometer or altimeter. Intended outcomes are that students gain an understanding that barometric or altimeter pressure varies and its increase or decrease indicates an upcoming change in the weather. Students also learn that the air has weight. Supporting background materials for both student and ... Full description.

The purpose of this activity is to record daily measurements of maximum, minimum, and current air and soil temperatures at a common site. One temperature probe is placed inside an instrument shelter while another is installed at a 10 cm depth in the soil. A digital thermometer is used to measure current temperatures as well as daily minimum and maximum temperatures. The daily minimum and maximum temperatures ... Full description.

The purpose of this resource is to understand what causes the Earth's seasons with a focus on the Earth's tilt and spherical shape. Students learn how sunlight spreads over the Earth at different times of the year, emphasizing the solstices and the equinoxes. Students investigate the effect of the Earth.s tilt on the spread of sunlight by modeling different tilts using a three-dimensional polyhedron ... Full description.

The purpose of this activity is to measure the total precipitable water vapor (column water vapor) in the atmosphere above an observer's site. Students point a GLOBE/GIFTS water vapor instrument at the sun and record the voltage readings from a digital voltmeter. They observe sky conditions near the Sun and perform the Cloud Protocols. Intended outcomes are that students understand the concept that ... Full description.

The purpose of this activity is to measure the aerosol optical thickness of the atmosphere (how much of the sun's light is scattered or absorbed by particles suspended in the air). Students point a GLOBE sun photometer at the sun and record the largest voltage reading they obtain on a digital voltmeter connected to the photometer. Students observe sky conditions near the sun, perform the Cloud, Optional ... Full description.

The purpose of the resource is to measure the different types of fuels for fires. Full description.

The purpose of this resource is to develop an understanding of the relationship between budburst and the environment and to help students recognize actual budburst when they are doing the Green-Up protocol. Students will do simple explorations to observe the relationship between budburst and temperature. This is a winter or dry season activity to be done prior to green-up observations. Full description.

The purpose of this activity is to measure air (and optionally soil) temperature within one hour of solar noon and the maximum and minimum air temperatures for the previous 24 hours. Intended outcomes are that students will learn to read minimum, maximum, and current temperatures using a U-shaped thermometer, understand diurnal and annual temperature variations, and recognize factors that influence ... Full description.

The purpose of this resource is to measure the salinity of the water using a salinity titration kit. Students will measure the salinity of saltwater using a salinity titration kit. Full description.