Edit: I don't know if this only happened to me or if others have found this, but once I finished this I'd unlocked... 35 items. Very strange. It popped on the one before my last one. So if you notice that it thinks you've unlocked more than you have, obviously start buying the cheaper ones.
Okay, this will take...a ridiculous number of points, 41,770 to be exact. (Edit: I SCREWED UP THAT NUMBER. Thanks BusyRich for pointing it out.)
Yes, that's right, 41,770. If you're lucky, you might get a couple hundred in one game for answer prizes AND a top 3 finish...if the game gives you that bonus. I've won several games with no bonus. $%@*#&@!!!!
I'd like to see the ability to earn points significantly increase... here's hoping. In any case...
Here's a list of what they are and what they boost. Thanks to everyone who gave info; I just wanted to make sure there was a list.
My suggestion is to hold off on spending KP until you can get the bow and arrow at 1820 KP. This adds 3 seconds for every question you complete (even if you skip or OUST), which makes it a LOT easier to finish more questions. Also use the answer spreadsheet that Shadow Kisuragi has started here (and please consider helping, since new questions are always appearing):
https://goo.gl/oQQ1pWThis is set to 9 items per row. I'm on PC. I've been told that this may not be the case for everyone.
#1 (10 KP): Rubber Duck: +5 seconds game time
#2 (20 KP): Baseball: +7 Seconds Game Time
#3 (30 KP): Comedy pin badge: +5 Sec game time, +1 Hint
#4 (50 KP): Jar of coins: +1 point/question
#5 (80 KP): Pizza: +5 Sec game time, +1 point/question
#6 (130 KP) Hammer: +1 bonus second/question
#7 (210 KP): Block of soap: +1 skips
#8 (340 KP): Flashlight: +2 hints
#9 (450 KP): Lucky Clover: +5 seconds game time, +1 hints
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#10: (520 KP): Typewriter: +5 seconds game time, +1 skip
#11: (640 KP): Swiss Army Knife: +1 skip, +1 hint
#12: (750 KP): Red Pepper: +2 hints, +1 skip
#13: (880 KP): Garlic: + 2 skips
#14: (1010 KP): Magic Crayon: +1 point/question, +1 skip, +1 hint
#15: (1050 KP): Micky the monkey: +2 points/question
#16: (1080 KP): Toy Robot: +2 points per question, +1 hints
#17: (1170 KP): Chatter Teeth: +2 points per question, +1 Skip
#18: (1210 KP): Russian Dolls: +1 points/question, +2 skips
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#19: (1300 KP): Top Hat: +5 hints
#20: (1350 KP): Butterfly: +5 hints, +1 skip.
#21: (1370 KP): Tree Decoration: +2 seconds/question
#22: (1400 KP): Egg: +5 seconds game time, +1 second/question
#23: (1470 KP): Broken Wrist Watch: +10 seconds game time, +1 second/question
#24: (1540 KP): Trainer: +3 skips
#25: (1620 KP): Diamond: +10 hints
**Achievement**#26: (1650 KP): Roses are red, violets are blue..., +2 skips, +6 hints.
#27: (1720 KP): Alarm Clock: +20 seconds game time, +2 bonus seconds/question
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#28: (1800 KP): Bowl and Chopstick Combo: +10 seconds game time, +1 second/question, +1 skip, +1 hint
#29: (1820 KP): Bow & Arrow: +3 bonus second/question
**Achievement**#30: (1870 KP): Potato: +3 lives
**Achievement**#31: (1920 KP): Police Badge: +2 Lives +2 Skips +2 hints
#32: (2010 KP): Pear: +20 seconds game time +2 Lives
#33: (2160 KP): Spectacles: +15 hints
#34: (2280 KP): SD Card: +40 seconds game time
#35: (2360 KP): Acorns: +3 points per question, +3 hints
#36: (2500 KP): The ring of randomness: +3 lives, +3 skips, +3 hints
Truly, best of luck in this grind.