Hello Wai Kit
If you are a pianist, The Young Bassoonist is very good and rapidly covers the first note "open F" down to low C diatonically in C and F majors. It uses familiar hymns, carols and folksongs (English based) and eventually includes chromatic notes from low F to 2 octaves.
Using the piano helps with motivation, intonation, tone development. It segues onto a number of pieces as well as the "not to be missed" Weissenborn Method. Progress is usually rapid especially for players with other wind playing or piano backgrounds.
The Topic: "Bassoon Scheme Beginner to High School Graduate" in this Forum expands on a possible programme for exactly your student's age-range, background etc.
Best wishes Neville
Christchurch New Zealand
Bassoonist / Teacher / Conductor