Children with Hairloss is another helpful organization for kids with alopecia.  Here is a direct quote from their mission statement:

"Our Organization was created as a resource for ALL CHILDREN who have medically-related hair loss. It is our mission to empower these children to become whole again by making hair available to those who may be financially challenged and might otherwise not have a means of obtaining the hair they want and need.

Our goal is to assist as many of these children as possible in changing their lives by improving their outlook and empowering them with a degree of self confidence that will allow them to face the world with renewed self esteem.
Our mission is to cover heads and heal young hearts."

They go on to say that:

For those who meet their requirements, they may be able to provide free hair replacements and complete care kits up to once a year until the age of 21!

If your child would like to apply for a hair replacement, please visit their website for more information.