As an introduction to bioengineering, student teams are given the engineering challenge to design and build prototype artificial limbs using a simple syringe system and limited resources. As part of a NASA lunar mission scenario, they determine which substance, water (liquid) or air (gas), makes the appendages more efficient.

Climates vary and understanding that water on earth reacts to the climate is a way to understand why water can be found as both liquid and solid on earth. Included in this lesson is a video of the activity in action, and an image of a world map.

Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.

By the end of this section, you will be able to do the following:

Describe the properties of water that are critical to maintaining life
Explain why water is an excellent solvent
Provide examples of water’s cohesive and adhesive properties
Discuss the role of acids, bases, and buffers in homeostasis

Learn the basics of why sweat cools your body down in this video. [5:13]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This overview of liquids explores what a liquid is and how matter becomes changes into a liquid.

"Matter is everything." So begins this comprehensive website on the physical and chemical properties of matter in its four main states: solids, liquids, gases, and plasmas. The text is large and easy-to-read. Students will enjoy the downloads, activities, and quizzes at this site.

Students are introduced to chemical engineering and learn about its many different applications. They are provided with a basic introduction to matter and its different properties and states. An associated hands-on activity gives students a chance to test their knowledge of the states of matter and how to make observations using their five senses: touch, smell, sound, sight and taste.

This article lists common misconceptions about states and changes of matter and the water cycle. It provides formative assessment probes and information about teaching for conceptual change.

Explore how water found in oceans, rivers, and other water bodies changes form and flows downward in these four videos produced by WGBH. Liquid water is found in water bodies across the planet. In locations where freezing temperatures occur, liquid water turns to solid ice. Students can use the video gallery to explore and identify characteristics of water and describe how water is found in different forms in different locations on Earth. An Activity, Background Essay, and Teaching Tips are provided.

Learn from NASA scientists about two forms of water (liquid and solid), and about the special properties of ice that are important to Earth's life and climate, in this video (2:35) from NASA eClips. Ice can be found in bodies of water across the planet. In the polar regions, ice that is present all year long affects temperatures and climates throughout the world. Students can use the video to understand different forms of water and to observe and identify ice in a variety of water bodies. An Activity, Background Essay, and Teaching Tips are provided.

Changes in energy are associated with both physical and chemical changes in chemistry. This pathway provides resources to explore how energy is related to phase changes, as well as chemical reactions.

Students are introduced to the engineering design process within the context of reading Dr. Seuss’s book, Bartholomew and the Oobleck. To do so, students study a sample of aloe vera gel (representing the oobleck) in lab groups. After analyzing the substance, they use the engineering design process to develop and test other substances in order to make it easier for rain to wash away the oobleck. Students must work within a set of constraints outlined within the Seuss book and throughout the activity and use only substances available within the context of the plot. Students also take into consideration the financial and environmental costs associated with each substance.

Discusses the changes of state that can occur for the three different types of matter (solids, liquids, and gases) and different types of heat energy that have been defined by scientists.

This expository article, written for students in grades 4-5, explains why ice floats and how this is essential to life on earth. Modified versions are available for younger students.

While learning about volcanoes, magma and lava flows, students learn about the properties of liquid movement, coming to understand viscosity and other factors that increase and decrease liquid flow. They also learn about lava composition and its risk to human settlements.

Why are some substances liquids, while others are solids? Why are some substances harder than others? Why is water essential for life on Earth? This pathway provides resources for answering these questions by looking at the types of intermolecular foces that exist between particles, and the effect that these forces have on the macroscopic properties of substances.

A series of interactive applets use scientific models to teach some basic concepts of matter, including states of matter and physical and chemical changes.