Deffinitely not, especially with border collies. they are in the top 5 most intelligent dogs currently recognized by any respectable kennel club. it shows that your dogs are on a nice path :)
No my puppies do that too.
Nope,not too young but still..smart puppy you have there. :D
No, it's not too young. Doesn't surprise me a bit.
It'snormal. I remember a puppy I had that was too small to dig a hole so covered up her bone with grass.
Some dogs hide bones, others don't. Border collies are very smart and your pup is following instinctive behavior. I have an 11 1/2 yr. old German Shepherd who has always done this, and then another one who never does it. One eats them as soon as possible, the other hides them and a week later goes and digs it up and enjoys it (ugh)... the muddier the better.