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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(No items are needed from your bedroom before school starts.)
- Talk to Dr Danner (the science teacher with the abnormally large forehead) and tell him "I'm not below average!" - he then sets you a challenge to find 5 different coloured flowers.
- Talk to Nugget, who tells you about being trapped. Talk to the Principal (blonde lady in pink suit) and tell her about Nugget - she'll send the lunch lady Margaret to guard him.
- Talk to Cindy, then talk to Carla - neither dialogue trees use apples here but are important to trigger events later in the day.
- Talk to Monty and pay him $3.00 to use the wheelchair ramp at the right of the school.
- Pick the blue flower.
(Collectables!)
- Walk to the corner of the school wall and interact when the red exclamation mark appears. You'll find the [HARD BOOGAR] Monstermon card.
- Walk over to the trees and read the sign. Remember this order: UP, LEFT, UP, RIGHT, UP, RIGHT, LEFT, UP. Enter the woods and follow this path. At the end, you will find the [LEGENDARY SWORD] Monstermon card.
- Enter the school via the wheelchair ramp. Go up the main stairs and talk to the hall monitors to get a hall pass and the [MONITOR'S SASH] outfit.
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- Talk to Cindy - she'll give you a love letter to deliver to Felix, who is upstairs in the "smart" class. Leave the classroom using your hall pass and go upstairs.
- Enter the science class, give Felix the love letter. Tell him that Cindy isn't bad. Get kicked out of the science lab.
- Before you go downstairs, enter the girls' bathroom and talk to Bob about wooing Ms. Applegate with some flowers.
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Lunch
- Felix will come over and start talking to you about Cindy and her "vegan" diet. Go talk to Margaret (the lunch lady) and ask her for something vegan. She won't go yet, as the Janitor is still mopping the floor, but she'll go once he's done.
- Talk to Carla, who will agree to distract Stevie. With him gone, enter the teachers' lounge and grab the yellow flower.
- Talk to Margaret to get the vegan salad. Give it to Felix, then go to recess.
(Collectables!)
- During lunch, Ozzy will leave to use the bathroom, leaving his bag lunch unattended. Interact with it to get the [ONION] Monstermon card.
- As it's easy to reload and restart sections of the day in Kindergarten 2, we can deviate from the story here to grab a Monstermon card. Instead of giving the salad to Felix, skip ahead to lunch. Go down the alley to see Agnes the dumpster hag. Trade her the salad for her cat Gravy. Talk to Cindy, who is jumping on the trampoline. Give her Gravy to get the [HAG'S RAGS] outfit AND the [POT OF GREASE] Monstermon card - then just reload the day from lunch - you'll still be able to keep the card!
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Recess
- Talk to Felix, who will give you some contraband to plant by the tree with the beehive. Do so, then call Penny over. Shake the tree and she'll be stung by the bees. Cindy will then give you the flower.
- Next, Bob will appear and give Ms. Applegate a bouquet of flowers, which will be conveniently left behind for you to grab a flower from!
(Achievement!)
- Follow Ms. Applegate and Bob to the teachers' lounge to see them making out - and to earn the K-I-S-S-I-N-G Achievement!
(Collectables!)
- Examine the fallen beehive to get the [THE TALLEST TREE] Monstermon card.
(Collectables!)
- Try to sell the "contraband" to Monty. Tell him you think it's worth more and he'll also throw in the [LITERALLY GRASS] Monstermon card.
(Collectables!)
- Climb the rock wall - the grey grips are unstable, so stick to the green and yellow ones. The [CASTLE OF SAND] Monstermon card is at the top.
(Collectables!)
- Talk to Jerome, by the swings. He'll give you a riddle to solve. The correct answer is: YELLOW, BLUE, BLUE, RED, BLUE, RED. Solve it and the [CYCLOPS DUCKLING] Monstermon card will appear.
- Sell the "contraband" to Monty for $5.00 (and an optional Monstermon card) so you'll be able to pay your lab fee.
- Go up the alley at the top of the playground to the dumpster. Pick the green flower that is growing nearby.
- Pay the lab fee and go to afternoon science class.
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Science Lab
- As you've managed to collect all 5 flowers, Dr Danner will leave the classroom and return with a carnivorous plant which he's named Diana.
- You're then tasked with solving the puzzle of what order to feed Diana the coloured flowers. Like Dr Danner says though, he got the answer by simply looking around. Look at the coloured fish and flasks in the background. The answer is: BLUE, YELLOW, PURPLE, RED, GREEN.
- You'll now be awarded with the key item [A+ Report Card] and the [MONSTROUS FLYTRAP] Monstermon Card.
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