Checkpoint

Let's put everything together in a checkpoint piece. Here's the original snippet:

Someone screamed.

The three of them stumbled into the hall, which was now full of kids. A sixth grader named Becka was the one screaming. She was holding her cell phone. “There’s no answer. There’s no answer,” she cried. “There’s nothing.”

For two seconds everyone froze. Then a rustle and a clatter, followed by the sound of dozens of fingers punching dozens of keypads.

“It’s not doing anything.”

“My mom would be home, she would answer. It’s not even ringing.”

“Oh, my God: there’s no internet, either. I have a signal, but there’s nothing.”

“I have three bars.”

“Me too, but it’s not there.”

Someone started wailing, a creepy, flesh-crawly sound. Everybody talked at once, the chatter escalating to yelling.

“Try 911,” a scared voice demanded.

“Who do you think I called, numbnuts?”

“There’s no 911?”

“There’s nothing. I’ve gone through half my speed dials, and there’s not anything.”

The hall was as full of kids as it would have been during a class change. But people weren’t rushing to their next class, or playing around, or spinning the locks on their lockers. There was no direction. People just stood there, like a herd of cattle waiting to stampede.

Gone(2008)

Here are the examples we've been building:

Someone swore loudly.

The three of them swivelled towards the noise, despite not being able to see anything. Scattered shoppers all started muttering at once. An annoyed voice came from the source of the noise. “Sorry! Stupid bloody phone’s not working! Can I borrow someone’s, please? I need to ring my kids.”

There was silence. Then pockets, purses and handbags rustled as people scrambled for their phones.

“Mine’s dead, too.”

“Sorry. Nothing here either."

“I’ve only just charged my phone. Why won’t it work?”

“My phone’s as black as everything else around here!”

“What the hell has happened?”

Another person swore, this time in what sounded like Italian. Everyone joined in the muttering and cursing.

“Is someone going to fix the lights, or what?”

“It’s got to be more than the stupid lights if our phones don’t work!”

“More than the lights?”

“Think about it, doofus. How can they all not be working?”

The supermarket was pretty full for a Tuesday afternoon. But, in the darkness, it sounded very different. No one was walking around, no trolleys were clattering, no beeping registers. Just muttering and boring supermarket music playing everywhere. It didn’t sound like that was going to last for much longer - it felt like rush hour was about to start.

There was the sound of shattering glass.

Trixie and the others turned to see the dude who worked in construction two doors down fly through his front window. He landed with a crunch on the lawn, rolled, and then jumped up, crying hysterically and swatting at himself. “Get it off me!” he was saying. Something dark was on his back, like a giant beetle. It jumped off and flew lazily away, over the roof of the man’s house.

Trixie looked at the others, who just stared back at her with their mouths open. And then it was like every house in the street opened up at once and everyone came out shouting.

“There’s a gator in my toilet!”

“My fern ate my cat!”

“Ants! Ants! The laundry’s full of giant ants!”

“The internet’s out!”

“It’s the biggest spider you’ve ever seen!”

Trixie's Gran came out of the house banging a metal pot with a metal spoon, like she was trying to scare off an angry ghost. “It’s a plague!” she screamed. “Repent!”

The neighbours went bananas.

“A plague? Like in the Bible?”

“It’s not a plague. It’s chemical warfare! We’re hallucinating from gas!”

“Someone call the police!”

“No, the fire department!”

“Call the army!”

There was something strangely comforting about everyone being out at once like this. It was like a block party. But everyone’s panic was starting to feed off each other. They were all bumping into each other, clutching at themselves, eyes rolling, babbling nonsense. And while everyone was freaking out, nobody was figuring out what was going on.

And below is your version, joined together. You might need to delete some excess paragraph breaks.

Is there anything you want to edit? This is your last chance to make improvements before we conclude the lesson!

Do you:

introduce a group of people other than your heroes?
show how they're reacting to your strange event (probably badly)?
have those feelings escalate?
describe the scene, hinting that things could get worse?

We've combined your snippets here. (You might want to delete extra paragraph breaks.)

High-concept storytelling in Gone 3: Ramping up