Low, dark clouds spit angry drops of rain onto the pavement, where they splattered into growing puddles of muddy water. Justin Grant kept his head down and plodded on toward school, trying to keep up with the much longer stride of Jordan Waters, his best friend since kindergarten.

Truth be told, neither was in much of a hurry to get to McNair Elementary. That was unusual, because both were good students and normally loved school, especially since they had formed the Math Kids club with Stephanie Lewis. The three had solved the mystery of the neighborhood burglars together, but the club had become complete when they’d added Catherine Duchesne. With their new club member, they had solved the mystery of a bank robbery and found a fortune in gold that had helped the town recover from financial hardship. They had also come in second in the district math competition.

But that was all in fourth grade. Now they were moving to fifth grade and things were changing—and not for the better.

For one thing, Catherine and Stephanie were going to be in a different classroom. The girls were going to be in Mrs. Wilson’s class while the boys were going to be in Mr. Miller’s. His nickname was “Miller the Killer” because he was so hard on kids. Some of the kids thought their fourth-grade teacher, Mrs. Gouche, had been tough too—they had called her Mrs. Grouch when she was mad—but the word was that Mr. Miller was much, much worse.

But that wasn’t what was bothering Jordan about their new teacher. It was math. Mr. Miller hated math. He had the only classroom in the entire school who didn’t have a math team in the school-wide competition. Mr. Miller loved English and social studies but made it clear that math was his least favorite subject. Jordan did great in math, but he struggled with English. He hated reading, mixed up letters when he tried to spell, and couldn’t stand writing papers. Mr. Miller was going to be his worst nightmare.

“This is going to be a lousy year, isn’t it?” Jordan said as he used his long legs to step over a puddle in a low spot in the sidewalk.

“Yeah,” replied Justin glumly. He didn’t even bother to try to step over the puddle. He was one of the shortest kids in his grade and he knew his short legs weren’t going to reach from one side to the other. He just plowed through the puddle, splashing water everywhere. He was glad he had worn an old pair of tennis shoes and not the new ones his mom had bought him.

“It’s going to stink not having Stephanie and Catherine in the same class,” Justin said as he shook water from one leg.

“Wouldn’t really matter, since Mr. Miller hates math anyway,” Jordan said. “I heard he doesn’t even have math groups.”

Justin didn’t reply, just trudged through the rain in his soaked sneakers. The first day of fifth grade was already miserable and they hadn’t even reached the school.

***

Four blocks away, Stephanie ducked her head and raced down the sidewalk and into the waiting dryness of Catherine’s dad’s car.

“Thanks so much for driving us to school, Mr. Duchesne,” Stephanie said politely, shaking a few drops of water out of her ponytail onto the floor in the back seat.

“Happy to do it,” Mr. Duchesne answered. “It’s right on my way to the college anyway, so it’s really no trouble. Besides, I still owe you one, don’t I?”

Stephanie smiled as she remembered meeting Catherine and working with the other Math Kids to solve the cryptic message Mr. Duchesne had left after he had been kidnapped. Teamwork and their math skills had helped them rescue their new friend’s father.

“Hey, check this out!” Catherine exclaimed. “My dad has a new book!” Catherine was positively beaming as she held it up for Stephanie to see.

Mr. Duchesne taught math at the college and had a whole library of math books, many of which he had written himself. Stephanie thumbed through the book, not understanding any of the equations but envious that Catherine’s dad was so into math. She is so lucky, Stephanie thought to herself.

“Congratulations!” she said. “I think it’ll be a while before anything in the book makes any sense to me, but I can’t wait to read it when it does.”

Mr. Duchesne chuckled from the front seat.

Stephanie placed her gym bag on the seat next to her. If the rain stopped in time, maybe her soccer team would still be able to practice after school. Soccer was one of the few things in the world that Stephanie liked as much as math—well, almost as much. Catherine looked longingly at the bag containing Stephanie’s soccer shorts, T-shirt, and sneakers. I wish I could play soccer like Stephanie, she thought.

“I can’t believe they split us up into two different classrooms,” Stephanie said.

“Yeah, it really stinks. Does that mean we’ll have to be on a different math team for the district competition?”

“Worse. It means we’ll actually have to compete against each other in the school contest,” Stephanie said gloomily.

“We’ll beat them, of course, but it won’t be nearly as much fun,” Catherine said.

Catherine smiled to show she was only joking, but Stephanie was worried. Would this be the end of the Math Kids?