With that being said, if you're pulling your hair out - here's the guide. Obviously, it contains SPOILERS.
(Click on the screenshots to enlarge them!)
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(Before school starts you'll need to pick up BOB'S TOOLBELT & the PRESTIGIOUS PIN BADGE)School Yard
- Talk to Monty and buy a lighter for $1.50.
- Talk to Nugget, who is trapped behind the sewer grate.
- Talk to Bob, give him his toolbelt and he will rescue Nugget.
- Talk to Nugget again and ask to be his friend. He will want a flower to prove your friendship.
- Talk to Bob and get access to the wheelchair ramp.
- Pick the blue flower and give it to Nugget.
- Return to the screen on the left. Talk to Nugget again and he will mention needing a lighter. Talk to Carla and pay her $1.00 to smuggle the lighter in for you.
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Morning Time
- Go to the regular class and talk to Nugget. He will ask if you managed to smuggle in the lighter, say yes.
- Nugget will distract Ms. Applegate so the two of you can go to the bathroom together to see the Janitor.
(Collectable!)
While Ms. Applegate is gone, you're free to steal items from the other kids' cubbies. There is a [HERMIT FROG] Monstermon card in the 3rd cubby from the left.
- Enter the boys' bathroom and talk to the Janitor. He needs his key. Go upstairs, and you'll be stopped by the hall monitor. Luckily, you have a lighter smuggled in to bribe him with!
- Enter the girls' bathroom and get the key from Bob. Go back to the boys' bathroom downstairs, give it to the Janitor and he will give you the shovel for Nugget.
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Lunch
- After the scene with Nugget and the lunch lady Margaret, talk to Nugget and he explains his plan, which involves buying all of the cafeteria's burgers.
- Talk to Margaret and buy a burger for $1.00.
- Then talk to Felix, show him your PRESTIGIOUS PIN and convince him to also buy a burger.
- Once Margaret leaves to make more burgers, go behind the counter and take the box of nuggets.
(Collectable!)
While you're behind the counter, check the corner close to the serving hatch. An exclamation mark will appear. This is the [MYSTICAL TOMATO] Monstermon card.
- Talk to Nugget, who will be saddened by the temperature of the nuggets and start banging his head on the wall. Keep talking to him until he stops.
- Go through the green door into the teachers' lounge and use the microwave to heat up the nuggets.
(Collectable!)
You can deviate from the story here to unlock an outfit and then restart the day from Lunch to continue the story if you wish. Instead of giving the heated nuggets to Nugget, skip ahead and let him keep banging his head. At recess, go up the alleyway and talk to Agnes the dumpster hag. Trade her a burger for a passbook. Go back into the cafeteria. Nugget is dying and asks to be buried in the nuggets. Do so, and you'll unlock the [FRIENDSHIP SHIRT] outfit.
- Return to Nugget and give him the microwaved nuggets.
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Recess
(Collectable!)
Another story deviation here to unlock a Monstermon card. Go up the alleyway and talk to Agnes the dumpster hag. Trade her the box of nuggets for her cat Tenders. Go into the teachers' lounge and buy a can of soda so Ms. Applegate will leave Nugget alone. Give Tenders to Nugget. You will get the [PALE TUNA] Monstermon card.
- Ms. Applegate and Nugget are having a dispute, it seems. Turn around and go back through the cafeteria to the teachers' lounge. Buy a soda from the vending machine. Give it to Ms. Applegate and she'll calm down.
- Talk to Nugget, he will dig the Nugget cave, fill it with the nuggets and you can enter.
- Once inside, Nugget will ask you to dispose of the severed leg. Pick it up.
(Collectable!)
Another story deviation here! Once you've picked up the severed leg, examine the skeleton on the left. It has a wallet, take the money, you'll need it to pay your lab fee. Go to science class and examine the other severed leg on the far wall. Dr Danner will thank you for returning the other leg with the [ULTRALODON] Monstermon card.
- Once you've picked up the leg, Nugget will ask you to come to gym class with him. Skip ahead and do so.
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Gym Class
- Nugget asks to play dodgeball and it ends up being a 5 VS 2 match, with you on the weaker side.
- Use the leg to deflect the ball back at Carla.
- Nugget will take out Felix and Ted. Move up, then back to take out Jerome.
- Move down behind Nugget, you will catch the ball and win the game.
Upon completing the storyline you will unlock the key item [MONSTERMON PLUSHIE] and the [DUNE WORM] Monstermon card.
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