So far in 2014, there have been few parties that have been better to one gender, and worse to the other. Let's start:
Prehistoric Party: Boy
Fair: Equal
Muppets: Equal?
Puffle Party: Equal
Funny Hat: Equal
Future Party: Boy
Prom: Girl
Penguin Cup: Boy
Music Jam: Equal (more to girl as in costumes)
Frozen: GIRL
Unknown event in Sept 2014: Either boy or girl
Boy: 3
Girl: 2.5
Equal: 5