Most yearbooks have the parents honor the students with a childhood picture and a phrase about how much joy they have brought to their lives. A twist on this would be letting the students honor their parents. A portion of the senior section of the yearbook could be devoted to students' messages to their parents, and include a favorite photograph of them together. This is a great way to thank parents for helping their teens navigate high school.
Create a senior section that lists everyone's favorite pop culture item. Include pictures of popular TV shows, books, movies and hobbies that teenagers did during this time. This section can serve as a mini time capsule for the graduation year, and it will provide lots of laughs and nostalgia later.
Ask every senior to submit their favorite quote. It can be funny or serious, and it can come from any source ranging from a philosopher or author to a favorite TV show or movie. This can provide a little information about the person that chose it and what was important to them at the time. Reading everyone's different quotes will be interesting and intriguing.