BrainPop

Brainpop is an educational website that uses numerous cartoon series to teach children (Grade school through high school) different concepts ranging from the Pythagorean theorem to Martin Luther King to the Urinary system.

The most prominent, and likewise popular, of these series is the "Mysteries of Life" cartoons, which follow Tim and Moby as they answer fan-mail, explaining a different educational concept with each one. Tim is a teenage boy and the main character of the series. Moby is his orange robot.

Other recurring characters are Cassie and Rita, two of Tim's friends who appear in many "Mysteries of Life" videos, along with having a series of their own. There is also Bob, a lab rat who appears in several shorts.

There is a Brainpop Jr. section, which is for younger children, and features many Expies of the main site's characters. Oh, and Moby appears there too with a slightly different personality. Moby's alternate continuities can probably be chalked up to Rule of Funny.

Oh, yeah. And it costs money.

Tropes used in BrainPop include:

A Boy and His X: A boy and his orange robot.
Art Evolution: Tim & Moby looked horrible when they first appeared in 1997. In 1998, Tim looks much like an adult and Moby looks much better. For the 1999-2000 season, Moby got straighter lines.
Babies Make Everything Better: One episode shows a grown-up, married Tim and Rita with two children.
- It was the pregnancy one.
Black Bead Eyes: Any human and animal character.
Blush Sticker: Tim in the "Stress" video... Although in that case it was due to, well, stress.
Butt Monkey: Tim himself.
Continuity Nod: In the Fractions episode, many of the robots from other videos on the site, such as Little Jimmy and the Cycloids from the Capitalization video and the Hillbot from the Country Music video, show up at Moby's birthday party.
Distaff Counterpart: Cassie and Rita would be this to Tim and Moby. Cassie is more like Moby, with Rita being more of the Tim.
Double Take: At the beginning of one video, Tim has one when he sees a portrait of Moby wearing a suit, only to discover that Moby was actually imitating it.
Edutainment Show: One that is FUNNY!
Expressive Shirt: Tim's shirt, as it has a picture that is always related to the episode's subject.
Hypocrite: Tim in the "Plagiarism" video. It turns out Moby had written his entire speech on his blog beforehand.
I Ate What?: In the Fractions video, after eating a piece of Moby's cake:

Tim: Three-quarters of a cup of...motor oil?
Tim: I have to... go to the... bathroom.
(Tim runs to the bathroom, then we hear spitting sounds)

Incredibly Lame Pun/Incredibly Lame Visual Pun:
In the Hiccups video, after Moby, of course, gets the hiccups.

Tim: They're gone, huh? I didn't even know you had a vagus nerve!
(Moby reveals a Las Vegas slot machine in his compartment)
Tim: And that is quite possibly the worst joke we've ever done.

In the "Word Problems" episode, Moby said he's going to watch "Kung Fu Cowboys", leaving Tim alone. Instead, he watches "Kong Fu Cowboys"!
"I think we should use our potential energy to make kinetic energy and run!"
"Maybe that's the reason why robots aren't allowed at baseball games".
Intelligible Unintelligible: The robots speak in beeps, but humans can understand them.
Jerkass: Moby can be this sometimes.
- See the Digital Etiquette episode.
Medium Blending: The early episodes made common use of oil pastels, clay animation, crayons, and colored pencils rather than cut-out animation (used for the first 3 seasons).
Oh Crap: Tim, upon finding out that he has to talk about periods.
Once Per Episode: In each episode, Tim receives from Moby a letter asking about the episode's subject, and he reads it out loud. It was followed by him explaining information about the subject.
Shipper on Deck: See Babies Make Everything Better.
Shout-Out:
- The bus driver in the "Back to School" video wears a Star Trek uniform.
- In the "Capitalization," "Clauses," and "Multiplication" videos, Energon cubes from Transformers are mentioned.
- At the beginning of the "Robots" video, Moby is seen playing with R2-D2 and C-3PO figurines.
This Is Wrong on So Many Levels: The "Problem Solving Using Tables" episode.
Vocal Evolution: Tim sounded quite different in older videos, and he talked faster because back then dial-up was common.
Whole-Episode Flashback: In the "Back to School" episode, Tim slides away many props from earlier episodes such as a breast pad from the "Period" episode, 3D glasses from the "Vision" episode, a mask from the "Skeleton" episode, a letter from the "Heart" episode, and the hat from the "Hair" episode. (Hence, this episode is from 1999).
Writing Lines: Tim does this at detention at the end of the "Daylight Saving Time" video.