Just wanted to chime in since what I would have said was not already said. How old are your birds? They don't need extra calcium til they start to lay. It looks like you have a commercial feed, if they are laying is it a layer feed? If so, it will have a good amount of calcium and you have time to get to tsc and get oyster shell to then provide free choice, like your grit, btw nice pvc feeders! Yes, you can provide cleaned egg shells, crushed up good so as not to resemble eggs in nests- don't want to start bad egg eating habits , either in a bowl or on the ground.I am new also and have questions about oyster shells - or calcium supplements in general. I don't have any oyster shells and wasn't planning to go to TSC until next week. What else can I give to make sure they are getting enough calcium? I have read about crushed up egg shells - do I just sprinkle that on the ground or mix it with feed or mix it with scratch? Any other sources of calcium that are good for my girls?