“No, no. Don’t be silly,” said Mr. O’Cooper. “We’re not learning math. We’re learning about Ireland.”

  Mr. O’Cooper taught us a bunch of other stuff about Ireland, and it all involved addition, subtraction, multiplication, and division. Not fair! When he was done, you’ll never believe who came through the door.

  Nobody! You can’t come through a door. Doors are made of wood. I thought we went over that in Chapter 1. But you’ll never believe who came through the doorway.

  It was our music teacher, Mr. Loring! He said we should call him Mr. O’Loring on Saint Patrick’s Day, and he started singing a song.

  Oh, Danny Boy

  The pipes, the pipes are calling . . .

  That’s a weird song. If your pipes are calling, that means somebody must be stuck in your pipes. You need to call a plumber right away.

  “Follow me, everybody,” said Mr. O’Loring.

  “Where are we going?” Alexia asked.

  “You’ll find out,” Mr. O’Loring replied.

  He led us down the hall and out the back door to the playground. Beyond the blacktop is a big grassy area where we play soccer and stuff.

  “It’s time for our four-leaf-clover hunt!” said Mr. O’Loring.

  “Yay!” we all shouted.

  Mr. O’Loring told us that each leaf of a four-leaf clover has a meaning—hope, faith, love, and luck. He said four-leaf clovers are really rare. If we found one, he said, it would bring us good luck for the rest of the day.

  We got down on our hands and knees and looked for four-leaf clovers. Some of the teachers came out to help—Mr. O’Macky, Miss O’Small, and Mrs. O’Yonkers. Even Mrs. Patty was out there with Jake the Snake in a basket.

  “Would you like to touch Jake the Snake?” she asked us.

  “We already touched him,” I reminded her. “We’re looking for four-leaf clovers now.”

  We searched for a million hundred minutes. There were a lot of clovers with three leaves, but we couldn’t find any four-leaf clovers.

  That’s when I got the greatest idea in the history of the world.

  “Hey, Ryan,” I whispered. “Why don’t we just tear one of the leaves in half so it looks like a four-leaf clover?”

  “That would be cheating, A.J.,” Ryan whispered back. “If you cheat, you’ll have bad luck for the rest of the day.”

  What?! No way. What does Ryan know about four-leaf clovers? He’s not even Irish. I plucked a three-leaf clover from the grass and carefully tore one of the leaves so it looked just like a four-leaf clover.

  “Shhhh!” I told Ryan. “Don’t tell anybody.”

  “You’re pathetic, man,” Ryan said.

  “I found one!” I shouted. “I found a four-leaf clover!”

  Everybody came running over and gathered around to see my four-leaf clover.

  “Wow,” said Mr. O’Loring. “Nice work, A.J.! That means you’re going to have good luck for the rest of the day.”

  “Maybe I’ll catch a leprechaun,” I said, “and he’ll give me his pot of gold at the end of a rainbow.”

  Ha! I should get the Nobel Prize for coming up with that idea. That’s a prize they give out to people who don’t have bells. Ryan looked at me and shook his head.

  Everybody else was excited about my four-leaf clover, and they all got back on their hands and knees so they could find one too. That’s when the weirdest thing in the history of the world happened. While everybody was staring at the grass, I noticed somebody in the distance running near the back of the school.

  I only saw him for a second. It looked like a little man. He was dressed in green, with a green hat.

  “Hey, look!” I shouted.

  “Where?” Neil asked.

  “Over there!” I shouted, pointing at the door to the gym.

  The little man pulled open the door and ran into the school.

  “Who was that?” asked Alexia.

  Michael said, “I think it was . . . a leprechaun!”

  WHAT?! A LEPRECHAUN? I thought leprechauns weren’t real.

  Everybody stopped looking for four-leaf clovers. We all started yelling and screaming and hooting and hollering and freaking out.

  “Grab him!” Alexia shouted. “If we catch him, he’ll give us his pot of gold!”

  We didn’t bother lining up like Pringles. We just ran into the school.

  “Which way did he go?” shouted Neil.

  “This way!” Michael shouted. “Follow me!”

  We ran down the hallway past the gym, the band room, and the all-porpoise room. I don’t know why they call it the all-porpoise room. There are no dolphins in there. But there were no leprechauns in there either.

  “He must be hiding somewhere!” shouted Emily.

  We ran past the front office, the nurse’s office, and the art room, looking up and down all the hallways. No leprechaun.

  “He got away,” said Alexia.

  “Maybe he’s hiding in the teachers’ lounge!” shouted Ryan.

  “Good thinking!” I shouted. “We’re not allowed in there!”

  We ran down the hall to the teachers’ lounge. It’s a magical wonderland where the teachers get back rubs, lie around in hot tubs, and have servants feed them grapes all day.*

  I opened the door. Mr. O’Cooper was sitting there at a table by himself. It looked like he was grading papers. I didn’t see any hot tub or massage table.

  “Students aren’t allowed in the teachers’ lounge,” Mr. O’Cooper told us. “You kids know that.”

  “Did a leprechaun run in here?” I shouted.

  “No, why?” asked Mr. O’Cooper.

  “We were out in the playground,” said Michael, “and we saw a leprechaun run in through the back door. Now we can’t find him.”

  “A leprechaun in the school?!” shouted Mr. O’Cooper. “He may be in our classroom!”

  He jumped up from his chair and ran out of the teachers’ lounge. We all followed him. By the time we got to our classroom, I was panting. That means I was wearing pants.

  Mr. O’Cooper yanked open the door. And you’ll never believe in a million hundred years what we found in there.

  A mess!

  All our desks and chairs were upside down. Books and papers and colored pencils were scattered around. Our backpacks had been taken out of our cubbies and thrown on the floor.

  “What happened?” asked Emily. “Was there a robbery?”

  “No, this is what leprechauns do,” said Mr. O’Cooper. “They play tricks on you.”

  “Man, leprechauns are slobs,” I said.

  Mr. O’Cooper looked angry. He likes a really neat classroom.

  I noticed something on the floor near the door. It was a tiny envelope.

  “Look!” I said as I ran over to pick it up. “It’s a note!”

  I gave the envelope to Mr. O’Cooper, and he tore it open. We all crowded around him as he read it. This is what it said . . .

  Eeh eeh eeh

  !em hctac t’nac uoY

  nuahcerpeL eht yrraL—

  “What does that mean?” asked Emily.

  “Leprechauns are tricky,” said Mr. O’Cooper. “He wrote it in code.”

  “Maybe he reversed the letters!” shouted Neil.

  We read the note backward. This is what it said . . .

  Hee hee hee

  You can’t catch me!

  —Larry the Leprechaun

  Larry the Leprechaun! At least now we had his name. But we didn’t know where he was hiding.

  “What are we gonna do?” asked Ryan.

  “There’s only one thing we can do,” replied Mr. O’Cooper. “We need to make a leprechaun trap.”

  Yes! A leprechaun trap! If we could trap Larry the Leprechaun, we would get his pot of gold.

  “But first we have to clean up this mess,” said Mr. O’Cooper.

  Bummer in the summer! Making a mess is fun, but cleaning up a mess is no fun at all. We spent a million hundred minutes picking up all the stuff off the floor and turning our desks and chairs right side up again. By the time we were finished getting the classroom in order, it was time for lunch. We would have to wait to make our leprechaun trap.

  We pringled up and walked a million hundred miles to the vomitorium. It used to be called the “cafetorium,” until some first grader threw up in there last year. Ever since then everybody calls it the vomitorium. Mrs. Patty was greeting kids at the door.

  “Do you want to touch Jake the Snake?” she was asking everybody.

  “We already touched him,” Emily reminded her.

  Sheesh, Mrs. Patty sure is obsessed with that snake.

  “I’m so hungry,” I said as we got in line. “I could eat a hundred slices of pizza.”

  “I could eat a million slices of pizza,” said Ryan.

  “I could eat a trillion slices of pizza,” said Michael.

  But there were no slices of pizza to eat. When we got to the front of the line, we saw our lunch lady, Ms. Hall. I mean, Ms. O’Hall.

  “What would you like for lunch?” she asked cheerfully. “I’ve got green beans, green bread, green eggs, green muffins, green milk, green cupcakes, green doughnuts, green pancakes with green syrup . . . and corned beef and cabbage.”

  I thought I was gonna throw up.

  “Is the corned beef and cabbage green?” I asked.

  “Ugh, no!” said Ms. O’Hall. “That would be gross!”

  If you ask me, any food that’s green is gross. I couldn’t make up my mind what to eat.

  “Why don’t you start with some potatoes, A.J.?” Ms. O’Hall suggested.

  “In honor of Saint Patrick’s Day, I made baked potatoes, mashed potatoes, sweet potatoes, hash brown potatoes . . .”

  I wanted to go to Antarctica and live with the penguins. Penguins don’t have to eat green food and potatoes.

  “. . . garlic roasted potatoes, French fried potatoes, grilled potatoes, potato skins, potato soup, potato pancakes, potato salad . . .”*

  “Do you have anything that doesn’t have potato in it?” I asked Ms. O’Hall.

  “Well, the potato soup doesn’t have much potato in it,” she replied.

  I took some corned beef and cabbage and sat down at a long table with everybody else. They were arguing about whether or not leprechauns were real.

  “Larry the Leprechaun is probably just one of the teachers in disguise,” said Neil. “I bet he’s Mrs. O’Roopy. She’s always dressing up like other people.”

  “I say leprechauns are real,” said Ryan. “They wouldn’t put them on cereal boxes if they weren’t real.”

  “Don’t leprechauns make shoes or something?” asked Neil.

  “I thought they made cookies,” said Alexia.

  “No, elves make cookies,” said Michael. “Leprechauns make shoes.”

  “How do you get a pot of gold by making shoes?” I asked. “I don’t think shoemakers make a lot of money.”

  “Yeah,” added Emily, “and if leprechauns make shoes, how come there are no leprechaun shoe stores?”

  Good point.

  “If I got a pot of gold,” said Alexia, “I would use the money to take a trip around the world.”

  “I would buy a new video game system,” said Michael.

  “I would put it in the bank,” said Emily, “and use it to pay for college.”

  “I would buy all the candy in the world,” said Neil.

  “I would buy another pot of gold,” I said. “So then I’d have two pots of gold.”

  I should get another Nobel Prize for that idea.

  “That makes no sense, A.J.,” said Ryan. “If you used your pot of gold to buy a pot of gold, you wouldn’t have the first pot of gold anymore.”

  “Yeah,” agreed Neil. “You wouldn’t have more gold. You’d just have a different pot.”

  “That’s right,” said Alexia. “That would be like using four quarters to buy a dollar bill.”

  They were right. It was a dumb idea.

  It had started raining, so we had indoor recess. Boo! Indoor recess is no fun. We walked a million hundred miles back to our classroom. But when we got there, we saw the weirdest thing in the history of the world.

  The door was blocked by green ribbons.

  We ripped them off and opened the door. And do you know what we found in there?

  Green handprints. They were all over the place—on the floor, on the windows, and even on the walls. On the whiteboard in the front of the room, there was a message . . .

  Sorry for the tricks and trouble

  I had to leave here on the double.

  I’ll see you all another day

  With lots more tricks I need to play.

  Larry the Leprechaun had struck again!

  When Mr. O’Cooper walked into the room and saw the handprints all over the place, he looked really mad.

  “This means war!” he said.

  The war would have to wait, because it was time for art class. We had to walk a million hundred miles to the art room. Our teacher is Ms. Hannah. I mean, Ms. O’Hannah.

  “In honor of Saint Patrick’s Day,” she told us, “I thought it would be fun to cut shamrocks out of construction paper and decorate the walls of the school with them.”

  There were sheets of green paper and scissors out on the table.

  “Ms. O’Hannah,” I said, “can we make a leprechaun trap instead?”

  “Yeah,” said Alexia. “If we catch Larry the Leprechaun, we’ll get his pot of gold.”

  “What a wonderful idea!” said Ms. O’Hannah.

  She cleared the paper off the table and got a bunch of other stuff—Popsicle sticks, string, tape, stickers, green tissue paper, a glue stick, and a big cardboard box.

  She helped us cut a hole in the top of the cardboard box. Then we covered the hole with the tissue paper and the rest of the box with green paper. We glued a long stick to the side of the box and attached a string to the end of it so a fake gold coin would dangle over the hole. That would be the bait.

  Finally, we made a little ladder out of Popsicle sticks so the leprechaun could climb up on the box and fall into the hole when he tried to grab the coin.

  When our leprechaun trap was done, we stepped back to admire our work.

  “It’s cool,” said Ryan.

  “It’s awesome,” said Michael.

  “It’s sure to catch Larry the Leprechaun,” said Alexia.

  Ms. O’Hannah said we could take the leprechaun trap back to our classroom. We walked a million hundred miles back there and set it up on a desk in the front of the room. And you’ll never believe who walked into the door at that moment.

  Nobody! People don’t walk into doors! You’d bump your head.*

  But you’ll never believe who walked into the doorway. It was our school tech guy, Mr. Harrison. I mean, Mr. O’Harrison.

  Mr. O’Harrison fixes the computers and copy machines when they break down. He can fix anything.

  “What’s that contraption?” asked Mr. O’Harrison.

  “It’s a leprechaun trap,” said Mr. O’Cooper. “The students just built it during art class.”

  Mr. O’Harrison walked around the trap, looking it over. Then he let out a snort.

  “You call that a leprechaun trap?” he said. “That’s not gonna catch any leprechauns.”

  “It won’t?” we all said.

  “Nah,” said Mr. O’Harrison. “For one thing, it’s too small.”

  He was probably right. The leprechaun I saw running into the school was way too big to fit inside our trap.

  “I’ll be back in a jiff,” said Mr. O’Harrison as he ran out of the room.

  I don’t know what peanut butter had to do with anything. But a few minutes later Mr. O’Harrison came back. He was pushing a big cart full of wood, a hammer, nails, and lots of other stuff, including a big bell that looked like the Liberty Bell.

  “Leprechauns are tricky and sneaky,” Mr. O’Harrison told us. “If you want to catch ’em, you’ve got to be trickier and sneakier than they are.”

  He unrolled a big sheet of paper on Mr. O’Cooper’s desk. It had a drawing of a leprechaun trap on it. We all gathered around him as he explained how it worked.

  “Look,” Mr. O’Harrison said as he pointed to his drawing. “First, we lure the leprechaun over here with some cookies and gold coins. When he steps on this spot, he’ll bump against this string. That will knock over this line of dominoes. The last domino will hit this little car. It will roll down this ramp and bump into the baseball at the end. The baseball will roll down this tube and push this box of rocks off the table. The box of rocks will land on this bicycle pedal and turn it, causing these nails to pop the water balloon. The water in the balloon will slide down this marble run and knock down this bowling pin, which causes this wheel to spin, which activates this little zip line, which flips this switch, which drops the big bell that’s hanging from the ceiling. BAM! The bell falls on top of the leprechaun and he’s trapped!”

  “WOW,” we all said, which is “MOM” upside down.

  Mr. O’Harrison seemed to know a lot about trapping leprechauns. He’s probably trapped hundreds of them.

  “That leprechaun trap seems pretty complicated,” said Ryan. “Couldn’t we just flip the switch to drop the Liberty Bell on the leprechaun?”

  “No,” said Mr. O’Harrison.

  “Couldn’t we just shoot the leprechaun with a tranquilizer dart?” asked Alexia. “Or throw a big net over him?”

  “No!” said Mr. O’Harrison. “No self-respecting leprechaun is going to fall for that.”

  We started building Mr. O’Harrison’s leprechaun trap. It was hard work, and it took a million hundred hours. Attaching the big Liberty Bell to the ceiling with a rope was the hardest part. That bell is really heavy. We all had to work together to pick it up.

  “Where do you think Mr. O’Harrison got this Liberty Bell?” Ryan asked me as we were hoisting it up to the ceiling.

  “From Rent-a-Liberty-Bell,” I replied. “You can rent anything.”

  When we were finished, we scattered some cookies and gold coins around the floor to lure Larry the Leprechaun into our trap. Alexia made a sign that said FREE GOLD and put it next to the coins. We stepped back to admire our work.