How much is a penny that has the date of 1900 and another one has 1909 on it worth?

A 1900 Indian Head Cent is pretty common and only worth $1 or so in the condition most are found. 1909 was the first year of the Lincoln Cent and the last year of the Indian Head and there are 6 different varieties. A Lincoln with an S mintmark and the initials "VDB" near the lower rim of the reverse is a valueable coin. With the mintmark but not the initials it is still a pretty good find, with the initials but no mintmark it is worth several dollars, and with neither it is back in the $1 or less category. The Indian Cent with an S mintmark is scarce but without it is fairly common. Look just below the date on a Lincoln Cent or on the back of an Indian Head for the mintmark.