Clarinet
The clarinet is a very distinctive sounding instrument that lots of people love. It is very versatile with a wide range of pitch and volume. The most commonly played clarinet is the clarinet in Bb but there are a few other members of the clarinet family including the small Eb Clarinet and the bigger Bass Clarinet which are used frequently in orchestras and wind bands.
Here are some beginners books I recommend for Clarinet:
Abracadabra Clarinet by Jonathon Rutland (very suitable for children but can also be used by adults)
Clarinet Basics by Paul Harris
A Tune A Day by Paul Herfurth
It is possible to sit Grade exams on Clarinet and Jazz Clarinet. Here are links to information from the main Exam Boards:
https://gb.abrsm.org/en/our-exams/woodwind-exams/clarinet-exams/
http://www.trinitycollege.com/qualifications/music/grade-exams/woodwind/
https://gb.abrsm.org/en/our-exams/jazz-exams/jazz-clarinet-exams/
www.mtbexams.com