With regard to what to do with egg shells, I think there's something for everyone:
Cleaning Agent for Drains, Kitchen Pots, Etc.
You don’t have to use expensive, harsh, toxic chemicals to clean your drains anymore. Egg shells are excellent for this job, without any harshness to your hands, sink or drains. Just crush the shells as fine as you can and let them sit in the sink drain basket. Each time the water runs, the egg shells will make their way through to your drain pipes. Egg shells act as a safe, natural abrasive and will help to get rid of any grease or hair buildup, or whatever other unidentified refuse you’ve had accumulating. Be sure to save all your egg shells, enough to do all the drains in your home. You’ll find that your pipes will be cleared and flowing smoothly.
Put crushed egg shells into a dampened tea pot or thermos (especially a stainless steel thermos) that has been stained with tea. After letting them sit overnight, add a little water and swish around and empty into the sink (as not to waste them, they’ll help the drain pipes). Rinse the tea pot or thermos and you will immediately notice how the tea stains have been instantly removed. Excellent for this job, as the shells won’t leave an after taste or any lingering chemicals in your next pot of tea like bleaching might
If you are out of steel wool, drop a handful of crushed eggshells in with some water, add a drop of detergent if required and scrub them over pots and pans. The eggshells will clean off any residue. This is a good alternative while you are camping also. You don’t need harsh chemicals and eggshells are all natural for the environment.
Gardening/Planting
Crushed egg shells are excellent for the garden. Scatter them among your flower beds and/or vegetable gardens to keep cats from doing their business there. The shells are similar to crushed glass and irritates their delicate paw pads. This will deter them from entering and ruining your beautiful plants and vegetables.
To keep straight rows in your garden, use eggs in your seed mixture so you can see where the seeds are laid. Being organic, the egg shells won’t harm your garden areas in the least.
Eggshells are mainly calcium and magnesium, which are excellent compost sources. An advantage to using this all-natural fertilizer is that it discourages slugs from getting into your garden because they can’t move over the broken shells.
When planting seeds, mix crushed eggshells in your mixture. The assortment of shells and seeds will discourage birds and other small animals from eating your seeds.
For school age children, a neat project is to use a half eggshell as a planter. Put a little soil into the shell and plant a seed. The shell serves as a mini planter.
Eggs shells make excellent starter containers for seedlings. You can even set them in the cartons they first came in, providing your cartons are made from recycled paper. This provides an easy way to set your seedlings on a window sill so they can absorb the sunlight. The eggs shells are the perfect size, and being that they consist of calcium carbonate, they assist the new seedlings in absorbing nutrients from the soil. Once your plants are sturdy enough to transplant into the garden, they are easily removed by just cracking the shells. You can do that right in your garden area and allow the egg shells to remain where they are.
Some nutrients are released into the water from the eggs during cooking, which would be a shame to waste. After letting the water cool, use it on any of your plants that you feel need that little extra bit of a boost.
Egg Shell Art/Ornaments
If you happen to be artistic, you can make beautiful carvings from the egg shells. As you would with Easter eggs, poke tiny holes in the top and bottom, and allow the insides to drain out. When the egg is dry, you can begin your carving. There are many excellent sites on the internet that can give you ideas for patterns as well as directions and tools you’ll need.
Paint an entire eggshell in different colors. Crush the eggshell in a paper bag and you will be left with different colored eggshells. Create a mosaic or use the eggshells as glitter. Paint over with clear acrylic or glue that dries clear and you will be left with a colorful masterpiece.
By poking two small holes, one in the top, and one in the bottom of the egg, you can blow out the yolk gently leaving the eggshell in tact. Allow the egg to dry thoroughly. Once dry, you can use the eggs as unique decorations in baskets or wreaths around the house. You can also use glitter or paint to make Christmas decorations or Easter eggs by attaching a ribbon on top to hang them.
Feeding Egg Shells to Animals
It may seem cannibalistic, but chickens need calcium to make strong eggshells, and their own shells are a cheaper source than purchasing oyster grit. Recycle your eggshells by keeping them in a container for chickens to peck at as they need. It is important that the shells are pulverized enough that they are not recognizable as eggs, otherwise you may inadvertently encourage egg-eating behavior.
Eggshells provide an excellent source of calcium. When prepared properly, eggshells are a great addition to your dog’s diet.
