Here is the full list of all 24 Monster High - New Ghoul In School trophies - there are 6 bronze, 11 silver, 6 gold and 1 platinum.
All other Trophies Complete
Obtain all Clothing Items.
Save the School!
Find all the Shortcuts.
Upgrade the Casketball Court.
Complete Fashion Club Events.
Complete Cooking Club Events.
Complete Standalone Events.
Complete Environmental Club Events.
Meet all characters in Monster High.
Upgrade the Creepateria.
Complete Robotics Club Events.
Collect all Dusty Pennants.
Complete Comic Book Club Events.
Collect all Spirit Spiders.
Complete a Fundraising Event.
Collect all Cheer Steps.
Purchase Clothing Online.
Have over 1000 Spirit Coins.
Leave for School with a Tidy Room.
Ring the Bell in the Bell Tower
Complete first Fearleading Event.
Find and use a Locker Code.
Complete first Council Event.