Most beginning woodwind players start on flute, clarinet, or alto saxophone, and while these are all generally okay for most students aged 10-12 (when most kids start playing in the band), some consideration may be necessary for some students. For example, a small student with small hands may have difficulty completely covering the tone holes on a beginner clarinet. An instrument with covered tone holes (like an alto saxophone or flute) may be much easier to hold and finger.
Generally, woodwind instruments are started much later than piano and violin. The 10-12 age range is where many children are started with band instruments. This is due to the amount of concentration which is needed to succeed on the instrument. Ideally, woodwind beginners on the most common instruments (flute, clarinet, alto sax) should be able to sit and practice for 10-20 minutes or more without supervision. Woodwind instruments like the oboe and bassoon are more difficult because they require more studious and focused practice, especially in the beginning.
The recorder is probably the cheapest and easiest woodwind instrument to learn. The recorder is a good choice for children under the age of 10. Recorders are light, inexpensive, and easy to make a sound on. The fingerings are relatively similar to a clarinet, but the real value in a recorder is learning how to read music, keep time and breath well.
The flute is a common beginner instrument. It required a significant amount of air as well as breath control. Although the flute is relatively light, some smaller beginner students have trouble holding it horizontal or reaching some keys. There are specially-made “curved-head” flutes that make it a bit easier to manage, so that arm length or strength is less of an issue in the beginning.
The clarinet is another common beginner instrument! The clarinet also requires quite a bit of air, and special attention must be paid to the embouchure of the beginner clarinetist to properly seal the mouthpiece while permitting the reed to vibrate. Physically, make sure that you find a clarinet that is well balanced enough to be held with good posture and a correct bell angle without excess tension or discomfort. There are lightweight bells, thumb rests, and neck straps that can be used to make this instrument fit a wide range of students.
The saxophone is the last of the “beginner” woodwind instruments. While there are four common types of saxophones in use today (the soprano, alto, tenor, and baritone saxophones), the alto saxophone is the one that younger students will start out on. The saxophone shares many challenges of embouchure with the clarinet, having a similar (but slightly larger) mouthpiece and reed. Like the clarinet, the alto saxophone requires a reed that will need to be cared for and replaced on a regular basis.
The oboe and bassoon are generally considered more advanced woodwind instruments and are only rarely given to beginners. Both oboe and bassoon are double reed instruments, meaning that they use two thin pieces of precisely-shaped cane that are blown into and vibrate to make the sound. Learning how to form the embouchure for these instruments and shape the cane are both skills that are difficult for younger students to grasp. Oboes are held in a broadly similar manner to clarinets, although the double reed means that the angle of the oboe is even more important for proper sound production. Young players that are unable to hold the instrument “out” will not be able to form the proper embouchure with the reed. The bassoon is a very large and heavy instrument, and so holding this instrument is a challenge for smaller players. Most bassoonists use both a seat strap and a hand rest in order to adequately support the instrument and maintain a relaxed, correct hand position.