When Mammoth Island's new theme park, Mammoth Land, opens to the public, Troy and Olive are disappointed by the slowness of the rides. With help from the Inventor, they use steam engines to increase the velocity the Ferris wheel; but the wheel slips its moorings and runs rampant throughout the island. Topics covered: bevel gears, steam power, condensation.
Brenda opens a pizza parlor promising 'free mammoth delivery'; but due to the docile nature of the mammoths her profits are nil. The Inventor helps build a jet engine to deliver the pizzas on time. Note: this episode contained the first appearance of Mammoth Island's rival, Dodo Island. Topics covered: jet engines, combustion, flight.
Frank and Pilbeam try to help Brenda run an awning factory while the owner is away on vacation; but stumble on the principles of flight when an awning, tied to a mammoth's back, catches the wind. The Inventor teaches them how to turn this to their advantage. Topics covered: air pressure, flight, aeroplanes, wind.
Whilst working for the Inventor, Troy experiences several phenomenons due to the way light behaves, including a rainbow. Meanwhile, the Inventor has to contend with the loss of his piggy bank, leaving him penniless with several broken glass trophies to pay for. Topics covered: light, refraction, reflection, rainbows, mirrors, light rays.
When his water pipes freeze, the Inventor accidentally destroys Brenda's house, the local sauna, and his own house. Subsequently, Olive shows him the various ways in which mammoths are used to generate heat around the island, culminating in the construction of an enormous vacuum flask. Topics covered: heating water, conduction, radiation, convection currents, vacuum flasks.
The islanders guide their mammoth herd through a large canyon in search of fresh pasture, but lose them in various pits, ravines, and crevices after a stampede. The islanders become confused by the echoes of the mammoths' calls, and require the Inventor to construct a device to bring them all back. Topics covered: echoes, sound waves, hearing, ear anatomy.
Due to Pilbeam's inability to complete portraits of the winners of the annual Mammoth Island golf tournament, the Inventor suggests the use of cameras and lenses to speed the process. Meanwhile, Troy suffers sunburn. Topics covered: images, photography, binoculars, lenses, picture development, magnification. (pre-digital world)
In an attempt to beat Dodo Island, the islanders construct carts to deliver their cargo more efficiently to prospective buyers. All goes well until Olive and Troy, with a cargo of paper, reach a steep hill which they race down uncontrollably. The Inventor helps them add brakes. Meanwhile, Brenda and Pilbeam struggle to get a lovesick mammoth to take a bath. Topics covered: heat, friction, brakes, lubrication.
After Troy accidentally discovers the elastic properties of the Mammoth Island coconut trees, the islanders utilize them to gather coconuts effectively, by flinging them across the island, in order to gather 200 kilos to meet a 2-hour deadline set by a fruit salesman. Topics covered: springs, elasticity, Hooke's Law, mass, weighing.
To commemorate the opening of a new bridge, a musical concert is held, featuring mammoths as instruments, which ends in disaster when the Inventor cries out in pain, causing a stampede which wrecks the stage. The islanders ostracize him from the village until he can find a way to prepare a replacement concert in time for the bridge's opening. Against the orders of Frank, Olive assists him, and the pair set about building giant woodwind instruments. Topics covered: music, woodwind, brass, air flow, sound waves, instruments, vibration.
Brenda goes to market, leaving Troy and Pilbeam in charge of her house. After Troy accidentally washes Brenda's prized wedding ring down the sink, Pilbeam enlists the help of Olive, Frank and the Inventor to dig up the road and find it in the water pipes before Brenda returns. Topics covered: pressure, water pressure, plungers, water flow, suction.
When Troy and his mammoth both spear the same lemon with zinc and copper lances during the annual Mammoth Island lemon harvest, they receive an electric shock. Following this, Brenda and Pilbeam attempt to soothe the mammoth by grooming it with plastic combs; this creates static electricity, attracting litter from across the village. Subsequently, the Inventor explains the basic principles of electricity to the islanders who use the acidic qualities of lemons to help them power their machinery to increase the yield of the harvest. Topics covered: electricity, current, positive and negative charge, static electricity, acid, batteries, circuits.
Brenda inherits the Mammoth Inn, a decrepit mammoth-powered hotel, from her deceased Aunt Maude. When Frank and Olive arrive to collect their inheritance, Brenda enlists their help and the Inventor to repair the inn and modernize it with devices such as metal detectors, security cameras and smoke alarms. However, when a wealthy businessman expresses interest in buying the inn, but only if mammoths are present and the inn is not modernized, Pilbeam struggles to hide the machines. Topics covered: smoke alarms, metal detectors, lasers, escalators, sensors, counterweights, infra-red.
In the final episode of the series, the Inventor attempts to introduce a telephone network to Mammoth Island after the islanders begin using the dangerous method of flinging coded boulders to Dodo Island in order to communicate. Complications arise when the mammoths begin using the telephone poles as scratching posts, necessitating the use of mobile phones. Topics covered: telephones, exchanges, satellites, signals, mobile phones, fiber-optic systems.