I have a lot of wheat and memorial pre-1982 pennies, from which I've already removed the reds. I use them in my science classes and can ask students to sort them by year and even by mint, but is there enough advantage in doing so to go through the effort?
I think the real question is, what are your science students learning by sorting pennies by date and mint?
@Gaidzahg You didn't provide the age group for your students, but there is a lot more you can have them do, look for and learn! Explain RPM's and OMM's, CUDS, Die Chips. You could also get some information from a Red Book about the quantity of each date/mint mark were minted minted! You could also learn about the minting process and teach them about that! You might want to contact the U.S. Mint and ask if they have any age appropriate visual aids you could get! There is also a numismatic Resources section under the Forum tab where you can find more information. Good luck and welcome to CT!!!
Hello again and thank you! Glad to be here! The main use of the pennies is running experiments to show the different properties of copper vs. zinc. We compare their densities, their reactions with acid, their different melting points (a Bunsen burner is hot enough to melt zinc but not copper), and—if I can get my hands on liquid nitrogen—the different effects superlow temps have on malleability. The reason we have them separate them by year and mint is to then have them make a histogram, which they then analyze to answer questions like how does the frequency of a year change over time? or are there any years where it looks like something unusual may have happened? is the pattern linear or logarithmic? can you predict what the rarity of a particular year will be five years from now? and so on @1stSgt22 I do talk about all that stuff with the ones who really show an interest. In fact, we have a small coin club that meets once a month and goes through boxes of pennies I get from the bank. Thanks for suggesting contacting the Mint for visuals, I'm ashamed to say I never thought of that myself.
I wonder if you could predict what the mintages were by giving them one or two known mintages and using the relative frequency.
It could be interesting except pennies don't really circulate. They just travel back and forth in commerce so the location you are in the country will be the largest determinative of mint mark. The zinc pennies have a much higher attrition so will also skew the results. Dimes have too high attrition to make low mintages apparent; the sample size must be huge to get the '69 or '71 for instance. You'll get better results with quarters.