It was first thing in the morning, and Mr. Daniels’s hair was already a wreck. Field Trip Day was upon them!

Madison had forgotten her bus-sickness medicine and was afraid she’d puke. She wrote MY PUKE BAG on a paper bag and clutched it tight. Gopal was on the floor being a Mutant Alien Scorpion. One of the parent helpers decided to have a baby instead of come on the trip.

On the bus, Cody and Pearl sat together. Pearl had a sneaky-peaky look.

“I have a secret,” she whispered.

Pearl unzipped her backpack. She made her eyes go left-right, left-right. Wow. This must be a big secret, all right.

Now Pearl ducked down behind the seat in front of them. Cody ducked down, too.

When Pearl reached inside her backpack, Cody got a glimpse of something purple and sparkly.

“Are you ready?”

“Do bears — whoa!”

Cody could not believe her eyes. Gremlin! Pearl had brought him on the trip.

“What happened to him? He’s all glittery.”

“Shhh!” Pearl put her finger to her lips. “That’s claw polish. Isn’t it awesome?”

Gremlin looked so embarrassed. He was a fierce monster! He hated being glittery.

In a non-indoor voice, Cody said, “Don’t you know the official field-trip rules?”

“Shhh!” Pearl almost slid off the bus seat. She zipped Gremlin back inside, then sat up straight. Left-right, left-right went her rule-following eyes.

“I don’t know what came over me.” Pearl bit her lip. “I just couldn’t help it.”

“You took a wrong turn.”

“Right.”

“No, wrong.”

Pearl folded her hands in her lap. She looked worried.

“I won’t take him out,” she whispered. “I won’t even look at him again, I promise.”

Cody’s heart did a little dip. Pearl looked so sorry. She was a rule-follower, not a rule-breaker. She didn’t mean to do wrong.

But she really, really, really should not have stuck glitter on Gremlin’s claws.

The Insectarium was swarming.

With kids.

With bugs.

With excitement.

Mr. Daniels showed them the display of leaf-cutter ants. All the ants had jobs, he explained. Some gathered leaves. Some chewed up the leaves, then fed the pulp to their fungus gardens. Some were garbage collectors. And some were in the army.

“That would be me!” said Gopal.

The class watched the ants march back and forth through their tunnels. To keep the walls from caving in, Mr. Daniels said, the ants smoothed them with their own saliva. This was the nice word for spit.

Madison was not enjoying this.

“Can’t we see something cute instead? Like pandas?” She looked around. “And what is that hissing noise? There better not be any snakes in here!”

“No snakes.” Mr. Daniels smiled, like for once he was enjoying himself. Could he be a fellow bug-lover? “Follow me.” He led them toward a large glass tank. The closer they got, the louder the hissing grew.

Madison took one look and almost fainted.

“Dude!” cried Gopal. “Those guys are massive!”

“Behold,” said Mr. Daniels. “The Madagascar hissing cockroach.”

Reddish-brown bugs the size of baby carrots scurried around the tank. Some peeked from under leaves. Some climbed up the glass. A few were fighting, or something. Those were the ones making all the noise.

“Most invertebrates make noise by rubbing body parts together,” said Mr. Daniels. “But these fellows blow through air holes, just like us vertebrates. Their native habitat is an island off the coast of Africa.”

One of the cockroaches crawled up the glass and looked right at Cody. It had horns and fat, hairy legs. Its long antennas waved gracefully.

Hiss. Hiss.

“Why does everyone say cockroaches are gross?” asked Cody.

“Because,” said Pearl. “Most people don’t think for themselves.”

Cody made a mental note to ask Mr. Meen not to insult cockroaches any more.

There were so many wondrous bugs, it was impossible to pick her favorite. The giant walking stick, which looked exactly like its name? The luna moth, which looked like it was wearing an evening gown?

“Why choose?” said Pearl. “Just love them all equally.”

That was a lot of bug love. Cody smiled.

They ate lunch, and watched a movie called Bug Out! Too soon it was time to go home.

Quick-quick, Cody ran for a last look at the hissing cockroaches. One still stuck to the glass. Maybe he was trying to escape. That gave Cody’s heart a pinch. Maybe he longed for his island home, thousands of miles away.

“There you are!” A parent helper came rushing up. “Cody, you know the rule is to stay with your group at all times!”

“I’m sorry.”

As she turned away, the cockroach waved his long antennas. Cody waved sadly back.

The class was putting on coats and getting backpacks. Where was Pearl?

“I can’t wait to get out of here,” said Madison. “I feel like bugs are crawling all over me.”

Cody’s backpack hung beside Pearl’s. Who was still nowhere in sight.

Cody was a trusty person who would never go back on her word.

But she felt sad about that cockroach. She needed Gremlin to cheer her up. Quick-quick, she unzipped Pearl’s backpack. One tender pat, that was all!

Well, maybe just one little hug.

To her surprise, Gremlin waved his claws. This was monster for “Help! Help me return to my real home!”

What could Cody do? Nothing, that’s what. Gremlin belonged to Pearl now. Cody had to put him back, and she did. Only, oops, somehow she put him inside her backpack. Big mistake. And now she saw Pearl coming out of the restroom. Zip-zip! Cody closed both backpacks.

“You know what I was thinking?” said Pearl. “What if bugs look at humans and think, ‘Ooh, weird. Ooh, creepy’?”

“Ha-ha! That is so funny!” Cody’s voice squeaked like it needed oil.

“Are you okay?” Pearl looked at her.

Cody could only nod. Her voice was out of service.

On the bus home, the boys did Madagascar cockroach hisses. It got so loud, Mr. Daniels put them on Zone Zero. Not a peep!

That made it really easy to hear Madison puke into her bag.

Cody looked out the window. She hugged her backpack tight. That ride took two zillion years.