I'm young, 13 to be exact. I'm not old enough to join and I really want to help the brave men and women in the skies.How can I help the air force at this age?
As stated by Crossroads, AFROTC is an option. So is the Civil Air Patrol. Both will give you a taste of armed uniformed services life. Otherwise, look into volunteer opportunities locally to support the armed forces. Military.com may be a good start on researching charity organizations. Just be respectful in the forums, please.
In the US, you could look into Junior ROTC for the AF.
Study. Strive to become educated. Hone your intelligence. Learn science, engineering, and technology. There are two reasons for this:
The Air Force is a technical service, dependent most upon enlistees who are strong in science and technology. The air force prefers their enlistees to have degrees, and the more demanding jobs in the Air Force are filled by those with advanced degrees. For example, test pilots tend to have advanced engineering degrees.
The Air Force is expensive to maintain and depends upon a fair amount of tax revenue. If you do not enlist in the Air Force, but have developed strong engineering and science skills, you will have a higher than average salary that provides higher tax revenue to the government. The government will have more tax revenue to buy the airplanes and other systems that make the Air Force work for those who did enlist.
Whether you enlist or not, strengthening your own mind and your own knowledge of science and technology will help the Air Force.
There's probably little that you (or anyone) can do to help the Air Force directly without going through the training required to join as service personnel.
There is, however, another route. You could contact the Air Force Aid Society, a charity that provides support to the men and women of the air force to help with their non-operational needs (education, healthcare, housing, etc.). They may have a branch local to you that would welcome your enthusiasm.
Alternatively, there are many organisations supporting service veterans who could use your help. Take a look at Charity Navigator to find organisations that do what you're interested in, and contact their local branches.