Ships travelling between Lake Ontario and Lake Erie use the Welland Canal. Beginning with a conversation between characters Mathise, Geo, and Trig, they explain how a lock in the canal operates by gravity alone, without pumps. The characters use mathematics to solve problems such as how long the locks take to fill and how to express the volume and flow of water in more common terms (bathtubs of water ... Full description.

The purpose of this activity is to help students better understand percent cloud cover and to take more accurate cloud cover observations. Working in pairs or small groups, students use construction paper to simulate cloud cover. They estimate the percentage of cloud cover represented by torn pieces of paper on a contrasting background and assign a cloud cover classification to the simulations created ... Full description.

The purpose of this resource is to learn how to estimate data results in order to minimize errors in reading or recording data. Students participate in a game in which they collect data using various instruments and calculations and then try to fool other data collection teams by exaggerating some of the data numbers. They do this activity first with data describing objects in the classroom, then ... Full description.

In this activity, students build an edible aquifer using ice cream, food coloring, and other ingredients to represent the various layers. They will learn about groundwater, water tables, confining layers, contamination, and recharge. A link to a glossary of groundwater terms is provided. Full description.

Flowing water from rivers and streams is a valuable and plentiful energy resource that people learned to use centuries ago to operate the machinery that was important to their livelihoods. This page features diagrams (some animated) that show the three main principles of water; various types of water wheels; and the modern hydroelectric turbine. There are also animations of various types of mills ... Full description.

The purpose of this activity is to observe the type and cover of clouds including contrails. Students observe which of ten types of clouds and how many of three types of contrails are visible and how much of the sky is covered by clouds (other than contrails) and how much is covered by contrails. Intended outcomes are that students learn how to make estimates from observations and how to categorize ... 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 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 pH of water. Students use either a pH meter or pH paper to measure the pH. If using the pH meter, the meter needs to be calibrated with buffer solutions that have pH values of 4, 7, and 10. Full description.

The purpose of this resource is to teach students about the acidity levels of liquids and other substances around their school so they understand what pH levels tell us about the environment. Students will create mixtures of water samples, soil samples, plants and other natural materials to better understand the importance of pH levels. Full description.