For a writing teacher, Twitter has one or two real advantages. Young writers tend to think that whatever words that flow out of them are good enough, but Twitter's 140 character limit invites them to revise in order to make things fit. The quickest way to make something shorter is to make it general, but a teacher can help writers see how boring that is for readers. So that alerts students to the challenges of earning a real audience of busy human beings. And that leads to the idea that judgment and specificity animate our best writing and can guide revision. And that leads to more daring sentences from writers who are now putting themselves a little further out into the world. An example:

I was interested in tweeting about an idea in a video game review by Chris Suellentrop from the NY Times. Here is the source paragraph:

• What game designers lose in control, however, they gain in player attention. “Anything the player voluntarily engages with is going to make a much bigger impression than something they have no choice but to look at,” Mr. Gaynor said during his lecture.

What I cared about here--my own judgment, for my own purposes--was the idea that teachers could benefit from thinking about Gaynor's insight. I wanted to write a tweet sharing his idea and including a link to the article. But I could see that his sentence was too long to quote. Time to paraphrase, then. And I wanted to alert any teachers who were reading my Twitter stream that this tweet was for them. I began this way:

• Teachers, a clue from gaming:

And I reread the quotation from Gaynor in order to select the important ideas. Something about the things a player chooses to engage having a bigger impact than things the game chooses for the gamer. A teacher should see the value in that idea.

Notice the repeated words in my quick paraphrase--to me, this means that it can be made shorter somehow. Repeated phrases can be elegant and memorable, but they are often just wordy and lazy, so I assumed the worst about my rough paraphrase.

And I notice that my paraphrase is about the things chosen, not about the players who choose. That's not the right emphasis. I'm trying to claim a small insight about how learning works here, so the focus should be on the players who engage, not on the things they engage with. I understand my point better now as I revise.

I build a different paraphrase into my draft tweet:

• Teachers, a clue from gaming: Players engage more with things they have chosen for themselves.

That's still paying too much attention to the things and not to the players. Trying again:

• Teachers, a clue from gaming: Players engage more deeply when they get to choose what to engage.

Fine tuning now--no need to sound like a telegram even on Twitter. Make the phrases fuller, more natural:

• For teachers, a clue from gaming: Players engage more deeply when they get to choose what to engage. [Plus the link.]

Because it's writing, not math, there isn't a single right answer, a single best version of a tweet, but this process is an example of the way Twitter can help writing students pay attention to specificity, to attracting a particular audience by offering something that might matter to them, and to brevity that doesn't default to generality.