It can be very rewarding, a useful way of gaining work experience, improving confidence and learning new skills. If there is something you would particularly like to do then you could approach the organisation and ask if there are any volunteering opportunities.
Why not get involved with a local community group? For example, you could represent young people to share their thoughts and views so that decisions that are made are suitable for young people.
Find out what's going on in your area, or find out more about the UK Youth Parliament or the Hampshire County Youth Conference.