I'm sorry to hear of your difficulties. I have never seen or flown a Firebird Freedom, so I can only give you general advice.

It may not make you or your son feel any better, but I don't know of a single R/C airplane pilot who has not crashed more than once. It is never fun to crash, but it happens to everyone, from beginners to experts. You have to accept it as part of the learning curve and bounce back! It is totally worth it when you overcome your inexperience and start having successful flights!

If there is any possibility of getting an experienced R/C pilot to help you, that's by far the best course of action.

Also, read [link=http://www.rcgroups.com/forums/showthread.php?t=475834]this discussion thread[/link] and search for other discussions about the Firebird Freedom. You'll find you are not the first owner of the plane to have problems getting it to fly, but most people are eventually successful.

[link=http://www.rcuniverse.com/forum/m_3283662/anchors_3283662/mpage_1/key_firebird+freedom/anchor/tm.htm#3283662]Here's another thread.[/link]

[link=http://www.rcuniverse.com/forum/m_4071741/anchors_4071741/mpage_1/key_firebird+freedom/anchor/tm.htm#4071741]And another.[/link]

Search for "firebird freedom" and you find many more discussions.

If the prop is cracked, don't try to repair it; get a new one. If it was knocked loose but otherwise not damaged, you may be able to reattach it glue, such as Superglue or 2-part epoxy. But please, please do not let any glue run down the shaft toward the motor. The motor will be ruined if glue gets into it.

If the place where you purchased your plane does not have spare props and other spare parts, they can be ordered online from [link=http://www.horizonhobby.com/Products/RelatedParts.aspx?ProdID=HBZ7000&Category=Parts%20 Listing]Horizon Hobby[/link].

A few basic comments.
Did you fully charge the battery before flying? You might also want to try running the battery down and charging it up several times before your next flight. This sort of rechargeable battery takes a few cycles to reach its full potential.
Was the transmitter antenna fully extended?
Was the throttle all the way up -- fully "on" -- when you launched the plane?
Did the plane "feel" like it wanted to pull out of your hand and fly?
Since the plane did not climb, did you try adjusting the tail as shown in Step 17 (Adjusting the Climb Rate) in the instruction manual?

- Jeff