Another favorite of mine:
FAA advisory circulars (some free, others at cost) are available to all pilots and are obtained by
A. distribution from the nearest FAA district office.
B. ordering those desired from the Government Printing Office.
C. subscribing to the Federal Register.
The NTSB accident archives are overflowing with cases where failure to know the correct answer to the above was found to be the probable cause! So the finite time all students have is well spent learning the above.