BLUE SNOW CONES AND A KARATE MAN Our last day of middle school was supposed to be amazing, but instead Marco and I are standing at the sinks in the gray boys' bathroom trying to wash half a snow cone out of my hair. "And we were all excited when they said there were snow cones, too," Marco says. He's scrubbing my forehead with a paper towel. "It's always like that when they bring stuff to school. It's like you've never heard of that thing before, ever. Remember when the cafeteria had limeade that one time? And everyone freaked out completely? Running around all hyped up on limeade." That was two months ago, April 9th. I don't even have to check our case file to know that.

Limeade Day is still a legend around here. Snow Cone Day was supposed to be, too. It's this big celebration for the last day of school. I think the universe has tapped into how completely I do not want to celebrate the last day of school. "That hurts," I say. He stops rubbing. "Sorry. Here.

" He hands me the paper towel. I sponge my forehead for a while, but the color isn't going anywhere. "You should embrace it," Marco says. "Blue hair." "I don't want blue hair." "You look like a rock star." He's gone from sounding sympathetic to jealous in less than a second. That's pretty much the most Marco thing in the world.

I say, "You have enough rock stars in your life." "If only." He leans against the sink, all dramatic. He isn't even pretending to help me rinse my hair out anymore. "If only, if only, if only, Stephen." I dunk my head under the faucet. When I come up for air, he's watching me in the mirror, his face completely earnest. It's like I said.

Marco can change his entire face in the amount of time it takes me to blink. It's like I never know exactly who I'm going to be talking to. He says, in a voice to match his face, "That was really cool of you, you know?" "Trust me, I know." I put up with a lot for this kid. He says, "Getting in the way like that." Yeah. I took a hit for Marco. What else is new? "Eh.

I was already there. It's nothing." Then his expression breaks, and he gets sarcastic and smiley and jams his tongue into his cheek. "Stephen, you're my faaaaaavorite," he says, in this voice that's probably supposed to make him sound silly but really just makes him sound like he did when he was six. He messes up my hair with both hands, then he laughs at his blue palms. I decide that he's worth getting a snow cone thrown at me. I'm not always sure. But it's not like I had any other choice this time.

Luke and Chris said that if Marco didn't kiss me, they'd throw a snow cone at us. Marco didn't kiss me. They threw a snow cone at us. Except Marco's a way smaller target than I am, and I guess maybe I was in front of him a little, so most of it hit me. Anyway, it's pretty much the most straightforward thing that's ever happened to me in my whole life. Except, I guess nothing is straightforward when Marco's involved. And Marco's my best friend, and when you have a best friend like Marco, he is always, always, involved. He drums on the lockers on the way to homeroom.

Any other day we'd be accosted by some hall monitor for being out after the bell, even though my hair and his stained shirt should count as a perfectly good excuse. But it's the last day of school. These halls are a totally lawless place right now. Some seventh grader runs past us spraying a bottle of Silly String. It streaks behind him like a flag. A seventh grader has Silly String, and Marco and I, eighth graders-almost ninth graders, now-are just going to homeroom like upstanding citizens or something. Marco isn't looking at me, but I can tell he's thinking the same thing I am: We should be doing something so much cooler than this right now. Marco and I are criminal masterminds.

We solve crimes and plan heists. We've apprehended more cell-phone thieves, and returned more lost puppies, and sneaked in and borrowed more gym uniforms from the office when we've forgotten ours than most thirteen-year-olds could ever dream of. Just because we're usually on the side of law enforcement doesn't mean we should be shuffling around like sheep on the last day of school, right? Honestly, this school owes us. Look at that fluorescent light bulb that always flickers in time, perfectly, to the words of "Hey Jude." Who do you think discovered that? And who do you think breaks into the janitor's office and steals all the light bulbs every time they are about to fix it? Marco, yeah. But I mean … I was there. I'm always there. He jerks his head toward the front door at the end of the hallway.

"Jailbreak?" "It's raining." It seems like it's raining all the time lately. He looks outside and sighs. "Yeah." "Wouldn't be any fun." "This is terrible. Worst day ever, Stevey. Worst day of my whole life.

" I should be used to him saying this kind of stuff. Marco is really dramatic, but, I mean, seriously? I'm the one walking around looking like someone spilled toilet cleaner on me. "There's cookies in homeroom," I say. I hope this is true. It's a rumor Sasha told me. I don't think schools know any other ways to celebrate things than to feed us. "Yeah. This is what we have to live for, Stephen.

Cookies in homeroom." Mr. Takeda gives us this long look when we come through the door, but he holds out the tray of cookies without saying anything. There's only one chocolate chip left, so Marco grabs it and hands it to me like he thinks someone's going to snatch it away if he doesn't. "Thanks," I say. Marco nods all short and confident. His secret agent nod. Mr.

Takeda is still looking at my hair. Everyone's giggling at us a little, but someone makes a noise like a sick sheep over in the corner. Like the world's happiest, evilest sick sheep. I don't even have to look to know it's Luke. Last day of school, I remind myself, over and over. If the snow cones had worked out, there would have been two good things about middle school ending. Now there's one, and I'll latch on to it. Last day of middle school means the beginning of three months without Luke.

And it means this is Marco's last day of Luke forever, because Marco isn't going to high school with us. I still can't believe it. Clinton Preparatory Academy. It sounds like a school for dogs. And Marco, for some reason, is actually excited about going. Marco glares at Luke for half a second on the way to his desk, then turns his attention, just like always, to a different boy at the edge of the class. Benji gives him a smile and a brief wave. Marco lights up.

I bite into my cookie and sink into my seat next to him. These didn't used to be our desks, but I bribed Daniel Rivera with boxes of leftover Girl Scout cookies-I have three sisters, I could repave my driveway with Girl Scout cookies-until he switched with me. Marco gave me a hard time about it at first, but he gave in when he realized that the seat next to my new one has a great view of the back of Benji's head. Besides, it's not like it's big news that I want to sit next to Sasha. "We were talking about our summer vacation plans," Mr. Takeda says. "Miss McGuire, continue where you left off, please." Sasha tugs a piece of hair by her ear.

I really like Sasha's hair. It's curly and really dark red, like the inside of a cherry. "Just that my parents think that the chances we're going to find real fossils are pretty small, but I've been doing some outside reading, and I think that if we go to some of the places that haven't been checked in a while…" I am trying to listen to Sasha. But Marco won't stop pulling on my arm. "What?" I whisper. He points his pen toward Mr. Takeda's desk. I immediately see what he's all scrunched up about.

There's an action figure, some kind of three-inch-tall martial artist, perched on top of Mr. Takeda's keyboard. There's a rolled-up piece of paper shoved under its arm. "Wasn't there yesterday," Marco whispers. It's his job to notice these things. Marco is the eyes and ears of our operation. We haven't done a simple reconnaissance case in a while. To be honest, we haven't done many cases lately.

Marco knows I need to start small again, I think. After our last case. Aimee raises her hand and tells Mr. Takeda that she's going to Paris and will also be playing a lot of paint ball. Now that Sasha's done talking, I have no reason not to concentrate on the karate man. I can pretend there's nothing else important in the whole world. I hardly even feel my sticky hair anymore. Marco digs a sheet of paper out of his backpack and scrawls me a note: Please confirm that the action figure is, in fact, a new item of interest.

Our usual notes to each other aren't this formal, but this one will end up pasted into the case notebook, so it's impor.