Find that everyday highway overpass bridges are more interesting than they appear. These ubiquitous structures deserve to be admired for their simplicity and practicality. Plunge into the principles of multi-girder spans, and learn that new construction techniques make highway bridges more efficient and elegant than ever.

In the first of four lectures on your house as a technological system, review the eight engineered subsystems that go into modern dwellings. Then discover the miracle of building codes, which ensure that every new house is safe, constructible, and reasonably economical without involving an engineer in each design.

Plunge into hydraulics, learning how force is transmitted from actuators to hydraulic cylinders through fluid-filled lines. Then use this knowledge to design and build a hydraulically powered mechanical arm that can grasp and manipulate a concrete block - controlled by four hand-operated syringes. Along the way, use 3D printing to fabricate several crucial parts.

What happens to the 150 gallons of water that the average person uses and then sends down the drain each day? Delve into wastewater disposal and treatment. Among the details you investigate are the S-shaped trap in a waste pipe and that most ingenious of plumbing fixtures: the toilet.

Take wireless communications to a higher level: space. First master the rudiments of rockets, orbits, and satellite operations. Then focus on commercial satellite services such as television, radio, Internet, telephone, and navigation. Calculate the ideal orbit for communications satellites, and investigate the workings of the Global Positioning System.

Get a taste of electrical engineering by designing and building an electric launch controller that will ignite your rocket engine safely. Design a circuit that meets all code requirements. Use Ohm's law to determine the number of batteries and type of resistor required. Also, get a lesson in proper soldering technique for assembling the circuit.

Begin a sequence of eight episodes on machines in the ancient world. After an introduction to the simple machines described by the Greeks, focus on land transport employing the wheel and axle. Discover that wagon technology reached a high level of sophistication in the Roman Empire.

Build your model ballista. Then construct two other types of catapult - the onager and trebuchet - designed such that they store the same amount of energy as your ballista. Field test all three to determine which throws a golf ball farthest. Will the winner be the weapon from the Hellenistic (ballista), late Roman (onager), or medieval era (trebuchet)? You may be surprised!

Follow the transfer of automotive power from the gearbox through the driveshaft to the differential and drive-wheels. Study working models of the universal joint and differential. Also explore the design of front-wheel drive, and peer inside an automatic transmission to expose the miracle of its smooth operation.

Get started on DIY project number two: use cardboard to build a tower capable of supporting a 100-pound gravity load and a 10-pound lateral load simultaneously. This exercise closely replicates problems faced by real-world skyscraper designers. In this lesson, use vector math to analyze the forces exerted on each structural element of the building.