Teens/preteens clustered in groups at the edge of the dance floor, some kids dancing wildly in the middle showing off moves & goofing off, scattered loners or pairs leaning against the walls, wanting to be part of the fun but too shy or unsure to move away from the sidelines, DJ with headphones, speakers, balloons, folded up basketball hoops, polished gym floor, girls touching their bangs, flipping their hair, pulling at tight clothes, touching jewelery as they scope out the boys, girls scurrying off to the bathroom in twos and threes or packing up to approach boys, lame decorations, dark lighting, a disco ball or lighting effects provided by the DJ, people hemming the DJ's booth, pleading for him to play a certain song, writing down song titles on a sheet for the play list, moving in and out of the gym to congregate in an area where snacks and drinks can be bought from a booth or canteen, boys talking with friends, acting aloof and watching the girls while pretending not to, teachers and parent chaperones leaning against gym walls, watchful & arms crossed, people flocking to the dance floor when a good song comes up, friends nudging friends toward a crush when a slow song plays, adults making passes through the washrooms to make sure there's no drug/alcohol use, a girlfriend with an arm around a crying, raccoon-eyed girl who was spurned or dumped, a slash of light cutting across the gym floor every time the door is opened to the bright hall beyond
Loud music, deep base thumping off the walls, people shouting to be heard, laughter, feedback from a mike, the DJ making announcements, a crinkly chip bag, the hiss of a pop can tab popping, girls gossiping, teachers handing out verbal warnings, heavy gym doors banging shut, crying, yelling, swearing
Hairspray, too much perfume/cologne, hair products, scented lip gloss, sweat, BO, taco chip breath, possibly a skunky pot smell, stale cigarette smells & booze breath.
Water/juice/pop/punch as provided by the school or canteen club, liquor snuck in, chips, chocolate bars, snacks or pizza as provided by the event coordinators, gum, mints, harsh smoke from cigarettes
Grabbing onto a friend's arm, jostling/bumping/nudging while dancing, toes stepped on, slinging arm around another's shoulders, holding hands, fingers nervously plucking at clothes, sweaty palms, fiddling with bracelets, pulling out a phone to text, hugging, arms around a warm waist during a slow dance, kissing, grabbing onto someone as a flirting method, dragging someone to the dance floor, stuffing hands into pockets, holding onto an icy drink, shouldering a bathroom door open, climbing onto a stage or speaker to clown around or draw attention to self, touching another's arm, collar or sleeve as a way to flirt, music vibrations felt through the floor in feet, laying a hand against a vibrating speaker
--The words you choose can convey atmosphere and mood.
I peered out from behind a cluster of girls as Mark made his way over Clarissa and her friends. With the loud drum solo blasting out the speakers, he had to lean right up to her to deliver my message. He probably had to shout in her ear too, which I kind of felt bad about, but from the way she covered her face and bolted for the bathroom the minute he turned away, she obviously understood that I was breaking up with her.
Jim leaned past the snack counter to get a glimpse of the wall clock. Why did he volunteer for these things? The noise from the gym sounded more like screaming lobsters in a boiling pot than music, and the way the kids in line pushed and shoved, the last thing they needed was more sugar. He rubbed at his temples and then rang in another sale. Somewhere out there was a bottle of Advil with his name on it.
--Similes and metaphors create strong imagery when used sparingly.
Example 1: (Simile)
Kids bounced and bobbed in time with the music like fizz from a glass of pop.
Example 2: (Metaphor)
Across the gym, Sara's gaze practically pinned me to the wall. She smoothed down the front of her short skirt and then started over, weaving past jerking bodies on the dance floor. I shoved my hands in my pockets, hoping it made me look bored, but inside my rock tumbler stomach chugged and lurched. Get a grip, Stupid. She's just a girl.