The original buffalo head nickels were first minted in 1913. They are no longer in circulation; production of them stopped in 1938. However, they are still of some value to collectors.
They stopped making them in the 30's. If you can read the year on it, it's worth something. not much, maybe 50 cents but thats alot of a nickel. theres a FEW that are worth alot, so if you have a bunch get them appraised.
Buffalo head nickels were made in a range of years. Some say they're worth a lot because they're rare, others say they're worth the same amount as a normal nickel.