1940 - 1945 pennies saw three transitions in their composition. 1940 - 1942 were made from 95% copper and 5% tin. 1943 saw the steel cents, and 1944 - 1945 were blended with shell casings from WW2. If you can be more specific on the date, mint mark, and condition, you will be able to learn the approximate value of your pennies. As for the St Louis Fair Indian Head penny; If you have the circularly encased penny, (again depending on the condition) you are looking at a value of $10 (very good condition) to $45 in AU. The "stamped", elongated (Train-rail elongated) cent, maybe $5 for the curiosity value.