What to do in a long boring flight?

Well i'm heading to Philippines soon with my parents and 1 brother to visit our family as we haven't seen them for a long time. Basically, the flight will take about 12 hours and i'm dreading the waiting process of the flight because i hate getting waiting. Do you guys have any good/fun ideas of what to do in a long flight. I have already thought of bringing my books from school to do some revision and homework, buying a magazine such as vogue or bringing a laptop/DS.