The coin collecting Merit Badge is and has been a scam since it was created. It shouldn't include bills or stamps, just because they are similarly collected.
When I got the badge the thing with bills was completely ignored because bills were not coins. No Scout Master ever agreed that should be included. Recently when I read the requirements in 2014, likewise those I have spoken too have removed some of the requirements for it and ignore them as well.
Things were added to bloat the badge to make it something "worth" getting, but not possible for all. #10 is especially impossible to do when you don't live close enough unless you sacrifice the worth of going to Philmont just to travel to a coin show. and the USMint site it just a storefront.
What they still do to replace that, like what they did with me, was just buy a US coin collecting book of some sort and given a test on it. It isn't like you wont need the book later if you intend to keep the coins and it will give more information than the USMint website after their redesign.
IF you want to do justice to the kids getting the badge, Throw the merit badge book out. Teach then what they actually need to know form a coin collecting perspective, not some random list of requirements for an elective badge on their road for Eagle.
Teach them thins like identifying the parts of the coins, all 86 circulating quarter types/designs (not counting varieties: Liberty forward), 3 circulating dime types (Winged Liberty forward) etc.
Explain why the designs changed and what the change commemorates. How the design change goes into effect. Franklin to
Kennedy half is a good example. Lincoln Bicentennial is another.
Teach them the weights of the coins and such to be able to identify them. I think one new requirement and maybe it was an older one also is to get a coin graded. You dont tell someone 14 to spend $50 for a merit badge for something they may never del with after and arent even getting their monies worth for. You are supposed to be teaching them things that coincide with school stuff in a more interesting way, and tools they will need for the future. Again Most of the elective badges are messed up especially the ones like collecting and back in the day computers because they are writtn by someone that has no knowledge of these things in real world use perspective.
so why some coins have reeds and others dont, is much more important than getting a coin graded.
By counselor I assume you mean at summer camp or a merit badge college/camp type thing. You should bring up with your Scout Master or your Council the problems mentioned here about the badge, and ask them how it can be changed to benefit those getting the badge with useable knowledge, not jsut busy work to get the badge.
Obviously not all badges should be changed, but always question if what you are teaching is worth teaching and helpful to those you are teaching it to. So you wouldn't remove CPR from the First-aid merit badge, but Coin Collecting isn't First-aid, and varies in how it is done from collector to collector. No 2 people collect coins alike, and only those things they do that are similar are the core of coin collecting: sorting your collection, keeping a record, having some way to view, store, identify them, etc. like handling, emergency care, personal safety after handling coins.
There is no 1 correct way to collect coins, and what is in the current book last time I read it, and the one when I got the badge, way not correct at all from my point of view. Just remember the merit badge is for teaching, not for wasting money of those getting t6he badge.People have different amounts of money they can just throw at a hobby as not all scouts have rich parents, and some may come from impoverished families and scouts might be the only activity they can afford. No point in making the scouts feel bad about their life just to get a merit badge.