Listen to "Let It Go"...
	Pro Sticker Book...

Visit either the "Frosty Magic" or "Fun in the Snow" Dream Stages when using your Dream Book. To the right of the starting position, you will see a blue snowflake/musical note icon. Walk over to it, and you will be given the option to "change the background music". Do so, and you will be able to hear the song "Let It Go" from Frozen in its entirety.

Upon collecting all 100 main stickers, you will be able to view the credits in the middle of the main Castleton hub world. Once done, you will then be given the "Pro Sticker Book". This book contains 15 additional stickers with expert challenges to complete. Completing each challenge will also grant you a wand recipe or holiday-related item. The new challenges are listed below.

Unlockable	How to unlock
Ace Ensemble Guru	Wear 150 different Ace Ensembles.
Crafting Guru	Make 140 different pieces of furniture at Chip & Dale's Workshop.
Double Rainbow Rhythm	Obtain all Perfect ratings when mining in the Rainbow Cavern in one session.
Favor Savior	Do 50 different favors for Castleton residents.
Fiery Flower	Obtain a Blazing Hibiscus Seed, then grow it in 100 Acre Wood.
Fishing Frenzy	Catch 30 different types of fish.
Harvesting Guru	Raise 65 different crops in 100 Acre Wood.
High Vaultage	Clear Castle Vaults Mission #6.
Legend	Clear 90 episodes.
Legendary Owner	Raise your Cafe Level to 30.
Life's A Dream	Visit 20 different Dream Stages.
Shiny Shut-Eye	Visit the Shiny Dream Stage.
Spice of Life	Collect 50 different outfit variations at Clarices's Fashion Counter.
Surfing? Sure Thing!	In Hawaii, surf at least 400 meters without falling off your board.
You're Not So Big	Defeat a World Boss Ghost variant.