A dream from the book:

The world was experiencing a great economic crisis. No one had any more money -- Artie had it all. The papers put the blame squarely on Artie's counselors. Rob peaked out his window to look down on angry demonstrators screaming for the blood of himself and Dennis, and a few were stirring an enormous vat of boiling tar beside a large pile of feathers.
"Artie, do you have everybody's money?"
A shrug.
"Where did you get it all?"
"Nowhere."
"You two Canadian Ambulance guys have really done it this time!" thundered Butcher's voice.
"Better call an ambulance!" jeered the Road Hogs.
The demonstrators began to rush the door. Only one man could save the day.
"Look -- up in the sky! It's a bird! It's a plane! No, it's Pete Ogrodnick!"
"The world needs its money back!" thundered Pete in a booming voice. Taking three powerful strides forward he grasped Artie's bulging attaché case and opened it to the wind. There was a clap of thunder and a flash of lightening, and the green of money filled the air. The demonstrators broke into applause and the band played "Happy Days are here again." Rob cheered himself hoarse.
"Geez, Rob, quiet down!" said Dennis, shaking his partner awake. "You'll wake up the kids!"

Copyright © 1984 Gordon Korman used by permission

Dennis figures he's found the perfect summer job when he fabricates a history of childcare and snags he and his friend Rob 'cushy' jobs as counselors on the JT Juniortours cross-country driving tour. He's in heaven over the idea of being paid to drive around America, site-seeing. The only thing he hadn't counted on were the kids he would be driving.

Away from home for the first time, five of his six charges are simply lonely and a little homesick. And being a part of Group Ambulance is a drag, but what can you do? But Artie Geller is a Rockefeller in a ten-year-old's body, determined to slip away from his counselors at every opportunity and set up new business opportunities.

Attack Jelly in New York and a gambling ring in Washington D.C. are only the beginning, and soon Dennis and Rob learn they not only can't control Artie, but that they have to hide every trace of his schemes from the Juniortours boss, to protect their own skins. Visions of beautiful female counselors are replaced by visions of bankruptcy as their money vanishes into tacky souvenirs… and soon even the FBI seems to be after Group Ambulance.