Is he taking the Spanish exams. or UK? If the latter, have you tried the Oxford home study DVDs?
Those DVDs are more than adequate for PPL purposes:
Oxford Aviation PPL Study Package
If you don't want the DVD route, try this package - everything you need:
Transair Private Pilot (PPL) Study Pack
There are more outlets than Transair.
For what it is worth, I feel he should go the self study route and he (you...) should invest in a comfortable high spec. ANR headset.
Which 5 has he failed to pass?