These young people want to do their part for the planet. Under the Maestro's supervision, they prepare a butterfly garden after learning that butterflies are an endangered species.

The Maestro tells his students about the famous "Biosphere" project in Arizona, the largest enclosed ecological system in the world.

In the first episode of this new cartoon series, Once Upon a Time... Planet Earth, deforestation issues are addressed from outer space... Just grow a few trees in a spaceship and plant them on land later!

Amerigo and his crew continue exploring the New World. Their water is almost gone. Fortunately, the river they're sailing on turns out to be the Amazon, so they won't die of thirst after all.

Amerigo Vespucci sets foot for the first time on the American continent. He collects all manner of plants and animals, only to drop them into the Amazon River.

Amerigo Vespucci sails for the New World to explore new territories discovered by Columbus, draw accurate maps, and find the true route to the Indies. As his ship approaches "Little Venice," or Venezuela, the crew comes into contact with some local natives.

It's back to the past, with the Once Upon a Time series. How did America get its name? Take a trip back to Renaissance Italy in this first episode of The Explorers to find out.

When Leon rescues Lea from a melting iceberg, she seems to be more willing to forgive him. But not until he realizes what he did to make her angry in the first place!

It's Métro versus Goldenbar in this epic battle between robots and humans. Will the humans finally subdue their former servants? Or will the robot rebels finally achieve their goal of world domination?

Leon's marriage is in trouble. His good friend is hatching a plot to help him win Lea back, but will it work?

With the humans producing new robot allies every minute, it looks like they should be able to stand up to the rebels. But will the rebel robots prove stronger than the allies?

When Lea leaves Leon for Orni the platypus, Leon tries to woo his wife with a poem. But will she fall back in love with his "torrid charm"?

In the hope of bringing an end to the troublesome robot rebellion, the humans are sending two robot emissaries of their own to the robot-occupied planet. But how will these guests be received?

Leon and Lea are a lion couple who are going through a bit of a rough patch. As King of the Jungle, Leon might think he can come home at all hours of the night, but Lea has other plans for him... The Latin phrase says, "Alea jacta est," meaning "the die has been cast." Here, it's Lea who's casting them.

The Maestro realizes that the reason behind the robot rebellion lies in their circuitry. But what could have caused them to turn against their human masters? Stay tuned...