These are interactive lecture-demonstration questions probe student understanding of fundamental concepts in the photoelectric effect.

With the help of simple, teacher-led demonstration activities, students learn the basic concepts of heat transfer by means of conduction, convection, and radiation. Students then apply these concepts as they work in teams to solve two problems. One problem requires that they maintain the warm temperature of one soda can filled with water at approximately body temperature, and the other problem is to cause an identical soda can of warm water to cool as much as possible during the same thirty-minute time interval. Students design their solutions using only common, everyday materials. They record the water temperatures in their two soda cans every five minutes, and prepare line graphs in order to visually compare their results to the temperature of an unaltered control can of water.

Students make a simple conductivity tester using a battery and light bulb. They learn the difference between conductors and insulators of electrical energy as they test a variety of materials for their ability to conduct electricity.

This task is designed to give students insight into the effects of translations, rotations, and reflections on geometric figures in the context of showing that two figures are congruent.

Students' first experience with transformations is likely to be with specific shapes like triangles, quadrilaterals, circles, and figures with symmetry. Exhibiting a sequence of transformations that shows that two generic line segments of the same length are congruent is a good way for students to begin thinking about transformations in greater generality.

This task has two goals: first to develop student understanding of rigid motions in the context of demonstrating congruence. Secondly, student knowledge of reflections is refined by considering the notion of orientation in part (b).

The purpose of this task is to have students think about the meaning of multiplying a number by a fraction, and to use this understanding of fraction multiplication to make sense of the commutative property of multiplication in the case of fractions.

This article from the free online magazine Beyond Weather and the Water Cycle provides appropriate science lessons for Grades K-5. The focus is on acquainting young learners with climate-change concepts that are not too complex for their grade level and will not frighten them. In each issue, the magazine develops articles around one of the seven essential principles of climate science. The author believes early lessons about water availability and extreme weather events will prepare students for complex climate concepts they will encounter in later grades.

Students analyze video clips of kids rolling down a hill on skates, scooters, and bikes to determine whether mechanical energy is conserved.

This active demonstration investigates the law of conservation of momentum using a person on rollerblades and a thrown medicine ball.

Students are introduced to the idea of improving efficiency by examining a setting that is familiar to many teenagers fast food restaurants. More specifically, they learn about the concepts of trade-offs, constraints, increasing efficiency and systems thinking. They consider how to improve efficiency in a struggling restaurant through delegating tasks, restructuring employee responsibilities and revising a floor plan, all while working within limitations and requirements. Finally, students summarize and defend their suggested changes in argumentative essays.

An interactive lecture in which students use data on feeding habits and habitat, skeletons, and DNA sequences to draw phylogenetic trees.

Illustrated instructions for constructing and planting in the Fast Plants deli-container growing system. This is a stable growing system that is easy to construct for all age learners, and works well for growing Wisconsin Fast Plants. Made from recycled deli-containers, these growing systems can be cleaned and reused for multiple years.

The construction of the perpendicular bisector of a line segment is one of the most common in plane geometry and it is undertaken here. In addition to giving students a chance to work with straightedge and compass, the problem uses triangle congruence both to show that the constructed line is perpendicular to AB and to show that it bisects AB.

Successful completion of this cooperative learning activity requires the active involvement of the individual, the small group and the entire classroom (collaboration). The goal is to make a simple task as complicated as possible by constructing a single complex machine.

This online quiz on sustainable development can be used in French language classes to prepare intermediate-level students for discussions on environmental topics. The resource is excellent for immersion and content-based instruction.

The objective of this subject is to understand the nature of manufacturing process variation and the methods for its control. First, a general process model for control is developed to understand the limitations a specific process places on the type of control used. A general model for process variation is presented and three methods are developed to minimize variations: Statistical Process Control, Process Optimization and in-process Feedback Control. These are considered in a hierarchy of cost-performance tradeoffs, where performance is based on changes in process capability.

This task is for instruction purposes. Part (b) is subtle and the solution presented here uses a "dynamic" view of triangles with two side lengths fixed. This helps pave the way toward what students will see later in trigonometry but some guidance will likely be needed in order to get students started on this path.

Standard 8.NS.1 requires students to "convert a decimal expansion which repeats eventually into a rational number." Despite this choice of wording, the numbers in this task are rational numbers regardless of choice of representation. For example, 0.333 and 1/3 are two different ways of representing the same number.

This task gives students word problems with a given a set of a specified size and a specified number of subsets. The questions ask the student to find out the size of each of the subsets.