How old is a nickel with a Indian head on it?

Indian head nickels were minted from 1913 to early 1938.

If your coin doesn't have a date on the front it was probably minted before 1926, but so-called "no date" nickels are not valuable. They usually sell for a quarter or so as culls or curiOSity pieces. The reason is that early-date Indian head nickels had a design flaw that left the date region vulnerable to extra wear. The cupronickel alloy used for 5¢ coins is relatively hard so the flaw didn't become evident for almost a decade. By that time hundreds of millions had been struck, and the dates eventually wore off most of them.