What does "kibble" mean?
"Talk about speedy! thought Wishbone. And there isn't even any kibble involved! 'Atta boy, Joe!"
I didn't understand what "talk about speedy" and " 'Atta boy" meant too.

I was reading a book and its characters were playing basketball.

Question

What does "kibble" mean?
"Talk about speedy! thought Wishbone. And there isn't even any kibble involved! 'Atta boy, Joe!"
I didn't understand what "talk about speedy" and " 'Atta boy" meant too.

I was reading a book and its characters were playing basketball.

Answer

It sounds as if Wishbone was a dog watching boys play basketball.  He was comparing them to what dogs do. 
Speedy= fast
 kibble= dry dog food which is used to reward dogs to do tricks.
Attaboy= a word used by pet owners to encourage their dogs after they have done the right thing, after they have been rewarded with a handful of kibble .

Answer

Kibble :
To bruise; to grind coarsely;

Attaboy:
 Used to show encouragement or approval to a boy or man.
Attaboy! That's the way to hit a home run!