With these coffee ground fossils, your kids can pretend they were on a real-life dinosaur excavation! An easy kid’s craft that’s doable any time of the year!
Why these fossils are so fun to make
We’ve made a lot of projects using salt dough, but we wanted these homemade fossils to look more aged. Kids will love creating their own fossils by using old coffee grounds, some cold coffee for color, and of course, salt and flour. The coffee grounds make the finished fossils look more realistic as if they are specked with rocks and dirt. The cold coffee adds a darker color, making them more earthy.
Crafting Tips
- Mixing up the dough is a great sensory activity. Allow kids to knead the dough together with their hands to finish the mixing process.
- Kids can try all sorts of objects to press into their fossil dough. We’ve used toy dinosaurs and a seashell. But honestly, they can use whatever they want to create texture!
- These work well as visual aids for science projects and make a fun Earth Day craft for kids.
- For younger kids, you may want to measure out the ingredients ahead of time, but older kids will enjoy measuring.
Supplies you’ll need for coffee ground fossils
- 1 cup of used coffee grounds
- 1/2 cup of cold coffee
- 1 cup of flour
- 1/2 cup of salt
- Wax paper
- Mixing bowl
- Starfish, seashells, small toy dinosaurs, or other objects for the impressions
- Cookie cutter, empty can, or a butter knife
Things you may find helpful
- Smocks to keep the kids from messing up their clothes
- Paper towels
- Newspaper or a plastic or vinyl tablecloth to cover the work surface
- Toothpicks and string to hang your fossil, optional
How to make coffee ground fossils
Kids should ask a grown up to save some leftover coffee and the grounds for this activity!
- Get a grown up to brew a small amount of coffee (you’ll only need ½ cup for the activity) and save the grounds. Allow time for the coffee to cool.
- Stir together the coffee grounds, coffee, flour, and salt, until well mixed.
- Knead the dough and then flatten it out onto the wax paper.
- Use the can to cut out circles (or the cookie cutters/knife to cut out fun shapes).
- Press the small objects firmly into the dough, to leave an imprint. Remove the object, and there’s your fossil!
- You can use a toothpick to poke a small hole near the edge of the coffee ground fossils if you want to hang it later.
- Let the coffee ground fossils dry and harden overnight (depending on how thick you make them, it could take longer).
You can hang your coffee ground fossils the next day, or use them in an archaeological dig!
More Science Themed Craft Ideas:
Coffee Ground Fossils
Kids will love creating their own fossils by using old coffee grounds, some cold coffee for color, and of course, salt and flour.
Makes: 8 fossils
Supplies
- 1 cup of used coffee grounds
- 1/2 cup of cold coffee
- 1 cup of flour
- 1/2 cup of salt
- Wax paper
- Mixing bowl
- Some small objects to make impressions in the dough Shaped cookie cutters work well.
- Empty can or a butter knife
- Toothpicks optional
- String to hang your fossil optional
Instructions
- Get a grown up to brew a small amount of coffee (you’ll only need ½ cup for the activity) and save the grounds. Allow time for the coffee to cool. For younger kids, you may want to measure out the ingredients ahead of time, but older kids will enjoy measuring.
- Stir together the coffee grounds, coffee, flour, and salt, until well mixed.
- Knead the dough and then flatten it out onto the wax paper.
- Use the can to cut out circles (or the cookie cutters/knife to cut out fun shapes).
- Press the small objects firmly into the dough, to leave an imprint. Remove the object, and there’s your fossil! You can use a toothpick to poke a small hole near the edge of the fossil, if you want to hang it later.
- Let the fossil dry and harden overnight (depending on how thick you make them, they could take longer).
Expert Tips & FAQs
- Mixing up the dough is a great sensory activity. Allow kids to knead the dough together with their hands to finish the mixing process.
- Kids can try all sorts of objects to press into their fossil dough. We’ve used toy dinosaurs and a seashell. But honestly they can use whatever they want to create texture!
- These work well as visual aids for science projects and make a fun Earth Day craft for kids.
- For younger kids, you may want to measure out the ingredients ahead of time, but older kids will enjoy measuring.
This post originally appeared on this blog on June 3, 2016 but has since been updated with new photos.
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Nancy Wilkens says
Do you think this would harden and hold on lightweight decorations like beads, shells, etc?
Amanda Formaro says
Any type of salt dough like this is temporary – it just doesn’t hold up too long (unless it’s put on a shelf and left alone) and breaks easily.
Ann Lauvray says
Can you use cofffee that was brewed the day before or does it have to be fresh?
Nikki says
Hi! I was curious, had anyone ever tried making this with cold brew coffee?
Kanae says
This project is what i want it to be, i always dreamed of doing things like this, its so creative!!!
Alissa says
Can you use kosher salt?
Lori says
Can you use wheat flour instead?
Heather says
Great idea. Would you be able to “bury” small toys in this dough and “dig” them out like an excavation. I purchased some from the craft store and my grandsons loved digging out the dinosaurs hidden inside? The only drawback was the table was covered in fine dust!
Sherrie spencer says
Hi would i be able to use this recipe to make seed bombs/discs that have the dried seeds added and people put on their garden beds and will break down into the soil?
Many thanks 😊
Amanda Formaro says
I’m not sure that flour should go in the soil :/
Beth says
Was reading comments as found this project to enhance a VBS craft. Flour will not hurt the soil, but salt will kill plants. History lesson, an invading army would salt the ground around a sieged area so no food could be grown. I know the post above is from quite awhile ago, but making seed bombs that contain that much salt would be like putting Round Up in your garden. Not good. Thank you.
Cathy Gott says
Awesome
Rasagna says
Hi Amanda,
I love this idea but can we bake them… Will they be permanent?
Amanda Formaro says
Due to the nature of salt dough, they are very fragile. If they are dropped, they will break. Baking or not will yield the same result.
Kortney says
I think you could put ModPodge on the outside to help keep it more in tact.
Sarah Caughell says
How many fossils will this recipe yield?
Amanda Formaro says
I would say safely you could get 8, but maybe 10.
Janalyn says
Hi Amanda,
If you bake the fossils, do you think that would help them hold up longer and not break as easily?
Amanda Formaro says
It might. But it’s still salt dough which is definitely fragile and can be pretty temporary depending on how they are stored.
Mimi says
Hi, great idea. Is there an alternative to wax paper?
Amanda Formaro says
Parchment paper would work
Katy says
How long would these last after they have dried? I was thinking about Christmas Tree ornaments.
Amanda Formaro says
Thye might be too heavy, plus they break easy if they hit the floor.
Tomas says
Lovely idea! Can you use this recipe to make “ceramic objects” and use them in day to day life? Plates, bowls, cups?
Is it safe to use to serve food and drinks from?
Amanda Formaro says
Hi Tomas. I’m afraid not. This is a delicate dough, will soften if it gets wet, and breaks easily. It is best used for children’s craft projects.
Pat says
Love this idea!
Amanda Formaro says
Thanks Pat!
Filipa Garin says
They look amazing! I’m just confused on one thing, on the ingredients it says 1 cup coffee ground and on the instructions it says you will only need 1/2 cup?
Amanda Formaro says
Hi Filipa! You need one cup of coffee grounds and 1/2 cup coffee :)
Mathi says
How can I make it dry completely faster? Could I bake them?
Amanda Formaro says
Yes you can bake them at 250 F – check after 1 hour, but could take up to 2.5 hours.
Kathy says
How long will I have to let it harden and dry if it doesn’t dry overnight?
Amanda Formaro says
Depending on how thick you make them, it can take up to a few days.
Paolo says
Hi, is it okay to use cold water instead of cold coffee?
Amanda Formaro says
Should be fine, they just won’t be as dark :)
Casey says
How far in advance can I make the dough without it hardening prematurely?
Amanda Formaro says
I would say no longer than 24-36 hours.
Donna says
if you do not have coffee grounds is there something else you can use instead?
Amanda Formaro says
Essentially that would just be salt dough. Use the recipe on any of these salt dough crafts here – https://craftsbyamanda.com/?s=salt+dough
Joyce Fisher says
Would this “dough” work for dog paw prints?
Amanda Formaro says
Hi, Joyce. I believe it should work for paw prints, though I’ve never tried it. If you do, be sure to let us know how it turns out :)
Karen says
How many molds does one batch make?
Amanda Formaro says
Hi Karen, 1 batch makes 3 molds!
Rene says
Do you have to use coffee or could you use water? I want to do this with my 170 seventh graders. I can get the used grounds from Starbucks. I would think water would work fine.
Amanda Formaro says
Yes you can use water. Using the coffee just tints the dough darker.
JoAnn Bainbridge says
Amanda, can you hang these coffee ground fossils outside in the weather?
Amanda Formaro says
I wouldn’t leave them out to get rained on. The dough could soften. You could coat them with an outdoor sealer, probably three coats at least, but I still couldn’t guarantee that would maintain the integrity!
Jennifer says
What do u mean by cold coffee
Do u mean unbrewed coffee?
So u would need used coffee grounds AND unbrewed c.g. ?
Amanda Formaro says
By cold coffee, I mean coffee that has been brewed and allowed to cool completely. :)
Emily Marie says
These are so cool! I would never have guessed they were made with coffee grounds. Great idea!
Amanda Formaro says
I love how the coffee grounds make it look like dirt from the dig!