This is the time of the year when aunts and uncles say "I just don't know what to get them. Have you any ideas?". Well maybe a jolly good geolgical read ......... here is one that might take your fancy: Supercontinent: Ten billion years in the life of our planet by Ted Nield of the Geological Society of London. The book considers the development of the theory of plate tectonics and more.
You might also consider A short History of almost everything by Bill Bryson (available in the school library which covers geological topics in an interesting and informed way or "Trilobite" by Richard Fortey of the Natural History Museum and former president of the GSL. The title rather tells you what it is about.
There are many other books that would help your studies or simply be of interest .... go on put one on your Christmas list