Theme for the Year
First of all, you should come up with an interesting theme. For instance, a theme like 'Going Green' can be quite interesting. This will also draw the attention of the students to the importance of being environment friendly.
A Joint Effort
A yearbook is meant for every student in the school. So, take ideas from everyone. You could ask the budding artists in your school to come up with appropriate themes and covers. Something like a design contest with a predetermined theme will help you get a whole range of prototypes for your yearbook.
A yearbook that has the calligraphic motto of the school flashing on the cover looks quite attractive. A quote in the middle with the name of the school at the bottom, along with the year will give the yearbook quite a novel look.
A picture of your school mascot on the yearbook cover is also a good idea. A way to make the cover interesting with this mascot is a collection of pictures of the mascot in different poses. It will add the fun element to your yearbook.
The photography club could be represented by a camera, the drama club represented by those masks, the music club by their musical instruments, and so on.
Certain abstract photographs, paintings that represent a particular event, or thought that can be interpreted in different ways, will also make a good idea for the cover. Going abstract will surely work well.
Sometimes, seeking help of professionals to materialize your idea on to paper is not a bad idea at all. There are various websites that provide you with help in designing yearbooks.
Maintain originality, and you are good to go. Whenever you design a yearbook, just travel ahead in time and think of the smile it will put on your face, when you see this book of memories after many years.