Eliza succumbs to peer pressure from a ""teenage"" elephant, which gets in the way of her closeness with Marianne on an overnight trip.

Eliza convinces a mother kangaroo that she can handle the responsibilities of baby-sitting. She quickly learns that this mischievous joey is more than meets the eye. After a close encounter with Tasmanian devils, Eliza is all too happy to relieve her duties and go back to being a kid herself.

With the commvee broken down in the desert and no water left to survive, the Thornberrys go through desperate measures to maintain their sanity. However, on the verge of dehydration, Eliza convinces her family to perform the rain ritual pictured in a nearby monolith. Everyone cheers as the rains pour down among them.

When Eliza gets a hunch that foul play has led to Darwin's disappearance, she sets out to rescue her long lost companion. To her dismay, she finds Darwin has become one of the most popular acts at an Indian palace where a young prince lives. It's up to her to prove to Darwin that friendship runs deeper than the glamour and glitz of showbiz.

Eliza finds a hero in a giraffe who can see distances with his height and warn others of approaching danger. However, to Eliza's dismay, the giraffe leaves the animals for his own needs. Only when Eliza herself is in danger does the giraffe return and realize his selfishness.

Eliza frees a hyena from captivity, but having never lived in the wild, it doesn't know how to survive. Eliza attempts to teach it, but it seems hopeless--until a wild boar threatens them and the hyena's natural instincts take over.

Darwin brings Eliza to his chimpanzee compound, and Eliza, who isn't used to the structure of the chimpanzee way of life, puts Darwin in an uncomfortable situation. After a fire starts, Eliza realizes the hierarchy is necessary for jungle survival. In the end, she apologizes for her lack of understanding and the chimp leader lets Darwin off the hook.

The Thornberrys discover that koalas are missing from their native groves. Eliza decides to unravel the mystery only to discover Kip and Biederman masterminding the evil plot. It is now up to her to stop the culprits from wiping out an entire species!

When the Thornberrys leave Australia for India, Eliza can't bear to leave her wombat friend, Emily. Even though she is told not to, she brings her along. Now Eliza is constantly forced to re-create Emily's habitat in order to ensure her survival.

The Thornberrys meet the Fensterkopfs who make false documentaries. The Fensterkopfs' kid lies to Eliza and gets them all stuck on a cliff. After the families barely escape an avalanche, the value of truth is learned by all.

To study and protect the snow leopards from extinction and a construction site that is threatening their survival, Nigel's mentor (thought to be lost for many years) has left civilization to be a yeti. Eliza discovers his identity, helps him fend off the construction workers, and reunites him with her father.

When the Thornberrys are in Finland for the annual reindeer races, Eliza feels left out. She single-handedly uncovers a plot to sabotage the races, and along with an equally excluded reindeer who didn't make the final cut, helps save the day by playing fair.

When a friendly polar bear is wrongly accused of vicious behavior, Eliza goes to great lengths to keep him from being harmed and learns the value of sticking by a friend in times of trouble.

When Eliza is told that ""Jake"" the turtle is the last one of his kind, she can't just let his species become another name on the extinction list. Enlisting help from other animals, she soon discovers ""Samantha"" and brings the two turtles together--blind date style. Eliza soon realizes that playing the role of cupid is not as easy as it seems.

After Eliza saves an arctic hare from a determined stoat, she learns that underdogs come in all shapes and sizes.

Eliza gets in over her head when she assumes responsibilities she can't handle. She is soon forced to don scuba gear and rescue a fumbling Nigel and a tumbling commvee under the dangerous waters of Australia.

The Thornberrys get stranded on an uncharted island, basking at first in all the beauty and the splendor, but discover soon enough that being marooned isn't all it's cracked up to be.

Debbie discovers Eliza ""talking"" to dingoes and threatens to tell her parents. Eliza, concerned about the possibility of being shipped back to the United States as a science experiment, seeks help from nearby Aborigines. Together they confuse Debbie into thinking it was just a bad dream.

When the Commvee is surrounded by angry seals, Eliza tries her own methods to get them to move. But she learns from her Inuit friend Jim that traditional ways have their value.

When Kip and Biederman cause an oil spill, Eliza must save her sea otter friends.

Eliza goes to desperate measures to help animals survive during tough times along the Skeleton Coast. Her good-will intentions, however, will soon cost her family their entire supply of holiday cheer--and their Christmas dinner!

When Donnie kidnaps an aye-aye for a pet, Eliza must return the ""bad luck"" omen to his home before the villagers hunt him down.

When the Thornberrys visit the !Kung people, everyone is shocked to discover that Debbie can click-talk. No one is more surprised than Eliza, however, who is only ""cured"" of her jealousy by a !Kung healing ceremony.

When Eliza ""accidentally"" reads Debbie's diary she learns that Debbie thinks she's an embarrassment of a sister. Debbie and Eliza have it out and learn the real truth about their relationship.

When a seemingly abandoned panda bear imprints on Debbie, Eliza doubts Debbie's ""parenting"" ability--until a monsoon convinces Eliza that Debbie can handle more than she lets on.