Question: what to do with a two year old on a plane?
Answer: Window Gel Clings. This is such a super easy thing to bring along, and it can make for some great play. ... 
Water Wow Books. ... 
Lacing Cards. ... 
Lift-Flap Books. ... 
DoodlePro Trip. ... 
Little Cars. ... 
Little Figures. ... 
Electrical/Decorative Tape.