If you buy him ANOTHER set of manuals then you are adding to the study load.
Why not buy a CRP5 Navigation Slide Rule or a subscription to the on-line question bank?
The Q Bank would allow him to see the style and focus of the questions. The CRP5 is expensive (for what it is) so would be a valuable present that would remain in service when active as a pilot, so a better 'keepsake' as well.
h-r
