Time travel exists but laws prevent you from going back to before time travel existed. One day while traveling you end up going back slightly further back than expected...
Miss Teetering took careful headcount as her students began boarding the train, touching each on the back of the head and softly muttering their name as she entered them into her handheld database. She peeked inside to make sure each kid was seated and buckled in while simultaneously scanning for the face in the crowd that matched the last name on her list. Finally she smirked and put a hand on her hip as eight year-old Matilda emerged from the throng of onlookers which surrounded the train, "Late again, are we Miss Haskins?"
"I'm sorry Miss Teetering, but there was this -- "
"Tut tut," Miss Teetering waved a hand before her face, as if to deflect away the oncoming load of BS that Matilda was about to send her way, "now sit please, dear. We have a tight schedule to follow, you know."
"Yes, Ma'am," the little girl nodded. A young boy about Matilda's size brushed against her before she could board and grinned.
"Can you believe we were here to witness this? What an historic moment in history!" the boy said.
Matilda slyly glanced over at Miss Teetering before answering, "I am told this is a day for the ages. And to take notes because there will be a test."
The boy nodded, "This is a day that I will tell my grandchildren."
Matilda shrugged, "I wonder if you're my Granddad..."
"Matilda! Two demerits," Miss Teetering scolded, "no time frame interaction with the people of this era. Now scoot on-board."
Matilda nodded slowly, "Yes Ma'am."
The boy, still grinning, said to Matilda before she disappeared through the sliding double doors of the vehicle, "I'll always remember where I was for Mankind's first manned launch to Jupiter."
"Me too," Matilda returned, "I'm on my History field trip back in time!"
The doors slid shut but Miss Teetering's sharp voice could be heard throughout the station, "Matilda! Shush."
And like that the train's running lights illuminated the area around the base. Of course there were no wheels, because it wasn't a real train. There weren't even any rails.
That's because it wasn't a vehicle in the least, just an oblong tube filled with seats for the students and hanging hand grips for the teachers and chaperones. It wasn't a vehicle, per se, because the tube never physically moved. No, that same platform would receive them a hundred years in the future.
I mean really, there was no need to put wheels on a time machine, was there?
The digital destination sign on the front of the time machine tube lit up brightly: NEXT STOP 3079 AD. Inside the tube, an excited murmur of the day's events were discussed between all the children. Miss Teetering made sure Matilda's safety belt was properly secured before calling out to the Time Pilot, "Mr. Conductor sir, we are accounted for and ready for our return trip!"
The big man who stood at the front of the tube with a neatly pressed uniform leaned one beefy arm against the door to his cockpit -- which was about the same size as a public restroom stall. He nodded at Miss Teetering and called out to everybody, "Our return trip should only take us five minutes, give or take, ladies and gentlemen. It'll be a quick one. I hope you kids all had fun today."
He was buffeted by a resounding and boisterous "YAAAAAAAAY!" before he chuckled and disappeared into his cockpit area.
"Does it worry you that the man entrusted with our safe return to our home timeline won't give us an exact time for our trip? I mean, as a navigator through time you would think that man could tell us our journey's length to the nearest nanosecond."
"I'm sure he could, Jimmy dear, but he didn't want to bore us with details."
"I don't think details are boring. I think I'd feel safer knowing more details of our trip."
"Keep seated, Jimmy. It won't be long."
There was an undulating humming which increased in decibels until the interior lights dimmed and all those aboard felt the familiar queasiness of time travel as one's stomach passed through the ages. After two minutes, there was a shimmy to the entire tube. None of the kids screamed, but little Cassie Uhlander in the back wondered aloud, "I don't remember that on our trip backwards. Does that happen often, Miss Teetering?"
"I'm sure it's nothing," she said, but in her head she answered, I have never before felt such a peculiar sensation, Dear Cassie. It is my dearest wish that we don't perish in some horrible time accident.
There was a DING! in the cabin, and the children excitedly began counting down from forty. Under a minute until they realigned with their own time. When they reached twenty-three seconds however, there was a severe rumble and the tube shuddered violently enough to make some of the kids scream.
"Never fear, never fear, children," Miss Teetering commanded with a voice as cool and as crisp as freshly hung linen.
The ride stabilized, and she continued with the countdown. Nobody joined her until she reached three, then two, and finally one. There was a gentle THUMP! as the time tube reasserted itself into their time stream, then some of the children cheered.
The pilot emerged from the relative darkness of his cockpit and smiled warmly, "I must apologize for that little bit of turbulence back there, kids. Trust me, it is as routine as a sunset. No worries, folks."
But "Routine" was not the first word to enter Matilda Haskin's head as the double doors softly slid open. For beyond them lay...