Eggs are a great source of protein, they’re full of vitamins and minerals and hey, they taste good too. But once you crack the shell and fry up them eggs, what good is the shell but tossing it in the trash? A lot more than you’d think.   
Here are 20 Things to Do with Eggshells that you might not know about.
  1. Composting:  Eggshells are rich in calcium with about 750 to 800 mg of calcium in each medium eggshell. Eggshells include lots of other nutrients that are great for plants. Just crush or grind them up and add to your compost.
  2. Fertilizer: Along the same lines, you can crush eggshells and sprinkle them into a hole right before planting to fertilize the soil. Then every two weeks, crush eggshells and sprinkle them around the base of your plants.
  3. Prevent blossom end rot: Tomatoes and cucumbers are especially susceptible to blossom end rot. Sprinkle crushed eggshell around the vegetables to prevent this and provide some calcium carbonate.
  4. Seedling starters: Need a place to grow seedlings? Take an eggshell, rinse, add a hole on bottom for drainage and crack the other end. Fill this end with dirt and one to two seeds. Once they’re ready to be planted, just crack the eggshell at the bottom and plant the young plant along with the shell.
  5. Pest control: Crush eggshells around vegetables and flowers to keep away snails, slugs and cutworms because they don’t like crawling over the shell. Should keep cats from using your garden as a litter box too.
  6. Fertilize indoor plants: Just as with your garden, eggshells are a great way to keep your indoor plants healthy. Add the shells to a container of tepid water. Put in a cool, dark place overnight and then add the water to your plants.
  7. Cleaning dishes: Use eggshells to clean pots and pans that are tough to clean. They work wonderfully as an abrasive.
  8. Clean vases:  Vases can be hard to clean since they’re so tall and slender.  Just rinse the vase with warm water, add a few crushed eggshells, fill with warm water, and then add a drop of dishwashing soap. Shake and rinse thoroughly.
  9. Remove coffee and tea stains: Have a mug that is stained, no matter how you scrub? Add in some ground up eggshells, drop them in the mug and add warm water. Let sit overnight, letting the eggshells absorb the stain.
  10. Whiten laundry: Just stick some eggshells in a mesh bag in your laundry and your white clothes will lose their grayish tint. I haven’t tried this myself. Has anyone tried this? Did it work?
  11. Feed them to chickens: Laying hens need lots of calcium and often need supplements in order to get that calcium. Calcium deficient hens lead to thin-shelled (and possibly shell-less) eggs.
  12. Homemade calcium supplement: Clean and sanitize the eggshells, let them dry, and then blend them to powder using a blender or coffee grinder. Spoon them into gelatin capsules or add them to smoothies for the extra calcium and other health benefits.
  13. Pet calcium supplement: You’re not the only one that can benefit from egg shell. Your pets can also use a calcium boost. Just add sterilized, ground eggshells to your pets’ food.
  14. Make homemade sidewalk chalk: This is definitely something to try for the kids. Grind up 5-8 shells, add 1 tsp of hot water, 1 tsp of flour, and food coloring. Mix together and then pack into toilet rolls till dried. Sounds like lots of fun!
  15. Coffee additive: Try adding an eggshell to the filter in the coffee maker. It will take some of the bitterness out of the coffee flavor and what’s left over in the filter is perfect for adding to your compost.
  16. Coloring: Rather than hard boiling eggs and coloring them, use the blow out method to remove the egg yolk. You can then color the eggshells.
  17. Eggshell mosaics: You can leave your colored shells be, or consider taking the colored shells, crushing them, and creating a beautiful mosaic. All you need are colored shells, card stock, a design, glue and tweezers.
  18. Gelatin molds: Want a clever gelatin dessert? Use eggshells as a gelatin mold. It can also be used to create egg-shaped chocolate treats. Just pour in some melted chocolate.
  19. Facials: Use a mortar and pestle to grind the egg shells (or I assume a blender would work as well) and then mix with egg whites. This makes a great facial, but be sure to let the mixture dry completely before you rinse it off.
  20. Use as a bandage: The membrane inside eggshells is perfect for bandages. Crack the egg, swipe some membrane, wrap it around the cut and let it harden.