Donald Chung stood in front of his classmates at the UCLA Extension school and started to throw a fit — well, as much as the mild–mannered student from Taiwan could muster.

"I don't know what he's trying to pull," Chung said. "The guy's a total flake!"

His friend Jiu Hua Zhang chimed in: "You said it!"

The students had spent a good portion of the class practicing these expressions as part of their "street talk" course. In many foreign countries, English classes start as early as pre-school. But thousands of students still come to the US to get what they can't get back home: the idioms, the catchphrases — the slang.

“My conversation is more academic, or more like an essay,” Zhang said. “I need to be more, like, American.”

She and Chung enrolled less than half a year ago at UCLA Extension's American Language Center, one of multiple schools throughout California offering street talk classes. Zhang wants to get all of the jokes on her favorite American sitcom, "The Big Bang Theory."

Chung would like to catch what commentators are saying during NBA games.

"I think it's very difficult to understand what they're talking about because they use some vocabulary I can't understand," he said, sounding frustrated.

Hip-hop as a second language

There's a lot to learn. But because slang is constantly evolving, there aren’t many teaching materials devoted to it. Texts get dated faster than you can say YOLO.

So teachers are often left to find their own method of teaching American lingo, in ways creative and resourceful.

English as a Second Language teacher Stephen Mayeux enjoys hip-hop. So he figured his students at UC-Davis might, too.

He crafted lesson plans around 1990s hip-hop. N.W.A.’s "Straight Outta Compton" has come in handy teaching reductions in English — for example, how “out of” gets shortened.

"They’re saying 'straight out of Compton,'” Mayeux said. “But I think a lot of people, especially Americans, we pronounce it 'outta.'”

Mayex shares his lessons with students outside of his Hip-hop as a Second Language class through his website eslhiphop.com.

He said some educators might frown on what he's teaching. But, as someone who's studied linguistics, he believes "you have to treat every form or variety of the language as if it’s equally complex and valid."

"So the English that a rapper or hip-hop artist uses is no better or worse than what a university professor is using," Mayeux said.

Fitting in

Mayeux also uses the music to take the opportunity to teach about hip-hop culture, and give the students some context for what it is like to grow up in America.

He said that he has many close friends from other countries, and a lack of understanding about pop culture can leave them feeling left out.

"They do experience a little bit of alienation," Mayeux said. "They feel like they can’t be fully part of the group because they’re not speaking the same lingo."

Judy Tanka, who teaches English at the American Language Center, agreed.

”You may understand every word of the lecture," Tanka said. "But when you have to go to your study group or you have to call a classmate, slang is going to be necessary."

Tanka tries to incorporate slang into her everyday conversation with her students. She stays on top of the latest lingo with the help of a daughter in her 20s, but she finds a surprising number of phrases have stayed popular through the decades.

When her students tried to make up an excuse for not doing homework, she told them, "I don’t buy that."

"And they looked at me. 'Buy what, teacher?' And then I explained and they loved it. Now they’re telling each other, 'I don’t buy that.'”

For the latest slang, go to the source

As a young man, David Burke had a knack for picking up slang.

His ears pricked up whenever he heard interesting phrases. He'd write them down on his arms, later switching to a tape recorder.

Burke went on to make a name for himself as "Slangman" and published a whole series of self-titled books in which he teaches slang not just in English, but in foreign languages.

He got the idea to teach American slang after hanging out with a French friend more than 10 years ago.

"Somebody ran up to him and said, 'Hey, Pascal, what's up?'" Burke said. "And he froze for a second and looked up and started checking the ceiling."

Now, at age 56, Burke gets the scoop on the newest slang by striking up conversations with young people.

"I saw a kid at the gym working out with a friend of his," Burke said, "and I said, 'Can I ask you guys a question, what word would I not know?'"

Recently, Burke brought his compendium of slang to UCLA's American Language Center for a special presentation before English language learners. To complicate matters, Burke told students, slang isn’t just about words.

”Americans use a lot of grunts — I’ll show you," Burke said.

"For example, 'I don’t know' becomes 'I dunno.' 'I dunno' becomes the shoulders-up grunt, 'uh-uhh-uh.'"

Burke got students to try out the "uh-uhh-uh."

"How many cars on the freeway right now?"

"Uh-uhh-uh."

ESL students at UCLA's Extension School Credit: Josie Huang

Like a cow

In the audience was Donald Chung and Jiu Hua Zhang. They hung on Burke's every word.

In their short time in the US, they've managed to incorporate slang into their everyday conversations.

Chung is a fan of "what's up!" Zhang says she no longer enters a room saying ”Good morning, everyone."

"We just say, 'hi, guys!'" she said brightly.

Zhang is feeling pretty awesome about this. Or as kids in China say: "hĕn niú” which translates into "very cow-like."

But Chinese slang — that’s a whole other lesson for another day.

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