i find that the easiest way to appreciate coins is to single out the lustrous ones, which for copper means those with any gleaming red or even orange color. Perhaps also sort them out by date in ascending order? It will then get a little more complex when you find out which ones are key dates, those with especially low mintage figures. The pennies were made in either philadelphia, denver or san fran and this will be easily identified by the absence of any mintmark( found right below the year), or the presence of a D or S mintmark. Then it gets even more technical when you get to errors, which