Students learn about contact stress and its applications in engineering. They are introduced to the concept of heavy loads, such as buildings, elephants, people and traffic, and learn how those heavy loads apply contact stress. Through the analysis of their own footprints, students determine their contact stress.

This short video and interactive assessment activity is designed to teach fourth graders about multi-step subtraction of weights with compound units (metric units) - word problems.

This short video and interactive assessment activity is designed to teach fourth graders about subtracting compound units in years and months.

This short video and interactive assessment activity is designed to give fourth graders an overview of conversion between units of weight (english units).

This short video and interactive assessment activity is designed to teach fourth graders about finding the different weight from tables (metric units).

This short video and interactive assessment activity is designed to teach fourth graders about subtracting capacities in compound units (english units).

Students are introduced to static equilibrium by learning how forces and torques are balanced in a well-designed engineering structure. A tower crane is presented as a simplified two-dimensional case. Using Popsicle sticks and hot glue, student teams design, build and test a simple tower crane model according to these principles, ending with a team competition.

Students examine the motion of pendulums and come to understand that the longer the string of the pendulum, the fewer the number of swings in a given time interval. They see that changing the weight on the pendulum does not have an effect on the period. They also observe that changing the angle of release of the pendulum has negligible effect upon the period.

Students explore how pendulums work and why they are useful in everyday applications. In a hands-on activity, they experiment with string length, pendulum weight and angle of release. In an associated literacy activity, students explore the mechanical concept of rhythm, based on the principle of oscillation, in a broader biological and cultural context in dance and sports, poetry and other literary forms, and communication in general.

Students experientially learn about the characteristics of a simple physics phenomenon the pendulum by riding on playground swings. They use pendulum terms and a timer to experiment with swing variables. They extend their knowledge by following the steps of the engineering design process to design timekeeping devices powered by human swinging.

This lesson introduces students to the art of designing an airplane through paper airplane constructions. The goal is that students will learn important aircraft design considerations and how engineers must iterate their designs to achieve success. Students first follow several basic paper airplane models, after which they will then design their own paper airplane. They will also learn how engineers make models to test ideas and designs.

This short video and interactive assessment activity is designed to teach fourth graders about total length in compound units (english units).

In this activity, students learn about creating a design directly from a CAD (computer-aided design) program. They will design a tower in CAD and manufacture the parts with a laser cutter. A competition determines the tower design with the best strength:weight ratio. Students also investigate basic structural truss concepts and stress concentrations. Partnership with a local college or manufacturing center is necessary for the completion of this project.

Students learn about regular polygons and the common characteristics of regular polygons. They relate their mathematical knowledge of these shapes to the presence of these shapes in the human-made structures around us, especially trusses. Through a guided worksheet and teamwork, students explore the idea of dividing regular polygons into triangles, calculating the sums of angles in polygons using triangles, and identifying angles in shapes using protractors. They derive equations 1) for the sum of interior angles in a regular polygon, and 2) to find the measure of each angle in a regular n-gon. This activity extends students’ knowledge to engineering design and truss construction. This activity is the middle step in a series on polygons and trusses, and prepares students for the Polygon and Popsicle Trusses associated activity.

Students are introduced to the concepts of torque, power, friction and gear ratios. Teams modify two robotic LEGO® MINDSTORMS® vehicles by changing their gear ratios, wheel sizes, weight and engine power, while staying within a limit of points to spend on modifications. The robots face each other on a track with a string attaching one to the other. The winning robot, the one with the best adjustments, pulls the other across the line.

This short video and interactive assessment activity is designed to give fourth graders an overview of metric capacity operations.

Sal discusses US customary units of mass or weight such as ounces, pounds, and tons. [3:39]

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The airplanes unit begins with a lesson on how airplanes create lift, which involves a discussion of air pressure and how wings use Bernoulli's principle to change air pressure. Next, students explore the other three forces acting on airplanes thrust, weight and drag. Following these lessons, students learn how airplanes are controlled and use paper airplanes to demonstrate these principles. The final lessons addresses societal and technological impacts that airplanes have had on our world. Students learn about different kinds of airplanes and then design and build their own balsa wood airplanes based on what they have learned.

This short video and interactive assessment activity is designed to teach fourth graders about using lists to solve multi-step problems with single units (metric capacities) - word problems.

This short video and interactive assessment activity is designed to teach fourth graders about using pictures to balance a scale (metric units).