We developed activity-based instructional units to introduce basic quantum principles to students with limited physics and mathematics backgrounds. To emphasize the practical applications of contemporary physics, we introduced concepts using the contexts of light-emitting devices such as light-emitting diodes (LEDs), fluorescent lamps, and glow-in-the-dark toys. As our standard of living becomes more dependent on the latest developments in science and technology, our students' literacy must be at a level that enables them to make educated decisions on science- and technology-related issues and their everyday applications. Students need to have at least a basic understanding of 20th-century physics and its applications in order to make informed decisions about them. Unfortunately, many physics teachers either exclude or spend very little time on modern topics such as quantum mechanics in high school physics courses.^1,2 The high degree of mathematical formalism and abstract nature of quantum mechanics is frequently given as a reason for not introducing quantum physics in high school physics courses.^3,4

Over the past few years we have been addressing these issues as part of the Visual Quantum Mechanics project. To enable a broad spectrum of students to learn quantum mechanics, we have developed a series of interactive instructional units that utilize hands-on activities and computer visualizations to introduce quantum principles. Two versions of the Visual Quantum Mechanics instructional materials have been developed — one called Visual Quantum Mechanics — Original⁵ for high school students and non-science undergraduates, and Visual Quantum Mechanics — The Next Generation⁶ for undergraduate physics majors, which is derived from the Original. Both versions focus on enabling students to make observations, develop mental models consistent with quantum principles, and then apply these models to other, related situations. This paper describes instructional strategies and computer tools that have been used and adapted from two instructional units in the Visual Quantum Mechanics — Original, and what introductory physics and physical science students can learn from exploring with everyday light sources. Materials for other audiences are under development.

The Visual Quantum Mechanics — Original instructional materials utilize a modified learning cycle in which student investigations of concrete phenomena precede and follow the introduction of abstract concepts.⁷ These materials are divided into four major, but relatively short, instructional units and two units for background review. The instructional units include the following:

"Solids & Light" — Students observe the light emitted by solids and gases to understand energy quantization in atoms and its consequences in everyday devices such as the LED.

"Luminescence: It's Cool Light!" — Students observe light emitted by luminescent materials such as fluorescent lamps and glow-in-the-dark objects to build energy level models that explain a variety of light-emitting processes.

"Waves of Matter" — Students develop a model to explain discrete energy states and to learn about the wave nature of matter by examining its applications to the electron microscope and Star Trek Transporter through visualization activities.

"Seeing the Very Small: Quantum Tunneling" — Students learn about quantum tunneling and its applications to a scanning tunneling microscope using a computer program.

"Potential Energy Diagrams" — Students review energy conservation through classical experiences involving Hot Wheels® cars or dynamics carts with magnets along the track. They explore how potential energy diagrams play an important role in understanding of the quantum ideas.

"Making Waves" — A basic review on some properties of waves including interference.