Surprise Rocks {& a Dinosaur Dig}

Whip up these super-fun Surprise Rocks with a simple mixture of sand, coffee grounds, and flour. Tuck whatever surprise inside you'd like, so long as it can go in the oven at a low temperature. -- With mini plastic dinosaurs, they're just perfect for a dinosaur dig! 

This project always makes me smile. 

Each year with my little first graders, I do a dinosaur dig ... featuring these nifty little surprise rocks hiding dinosaurs inside.  And they love it!  They think it's so cool to pretend to be paleontologists digging for fossils or dinosaur bones, never sure what they're going to find.

And these surprise rocks are truly so easy to make, the little bit of time invested in them is so, so worth the joy and fun they bring my students.  I would make these for them even if they took 100 times the effort!  Now, these are not edible ... it's the first non-edible recipe I'm posting, but they're so fun I hoped you wouldn't mind.

With just a little bit of sand, a bit of flour and water, some leftover coffee grounds, and a package or two of plastic dinosaurs (or other surprise!) from the dollar store, you can have yourself a batch of surprise rocks.  And here's how.

Start by combining some sand, flour, coffee grounds, and water in a big bowl.  It will be hard to mix, but just get it started a little bit with a spoon.

Then, knead the mixture with your hands, just like you would if you were making bread dough. 

I recommend taking off any rings you're wearing for this step... unless you want someone to get a real surprise in their rock!

The mixture will come together nicely, and look like this after your kneading is done.

I use plastic dinosaurs that fit in the palm of my hand as the surprise.  You could use any other little trinket that wouldn't be harmed by a low temperature oven ... or, you could use something bigger than this but would need to adjust up the baking time of the rocks.

To make a rock,  grab a hunk of dough.  To cover the dinosaur in my hand in the photo above, I took a hunk about this big:

Flatten the dough out into a pancake ...

... that's about this thick:

Lay your surprise on the flattened dough pancake and fold half of the pancake over it.

Then continue to fold the dough pancake up over your surprise ...

... until it's all covered.  Gently press the seams together to seal your surprise in.

Place the rocks on a baking sheet lined with parchment paper.

Finally, pop them in the oven for a while ... and they come out looking like this.  Surprise rocks!

For our dinosaur dig, I bury the surprise rocks in a little bit of sand in a plastic tub.  Each student then gets to pretend to be a paleontologist.  So cute!  They first look over the 'land,' scanning for an area that looks like it's a little different than the surrounding 'land.'  Once they've found potential dig spots, they use paint brushes to gently excavate their finds.

After they've got their finds excavated enough to be able to grab them with their fingers, they pick up a rock and clean it off with their brushes, inspecting it to predict what they may have found.  Their excitement builds ...

... until they're finally at a point where they can break their rocks open!  They give the rocks a big ol' squeeze ...

... and SURPRISE! ...  reveal what they've found.  T-Rexes and pterodactyls always get the most squeals. 

And, I can't say for sure ... I mean, I wouldn't really know ... but I think the adults usually have just as much fun breaking open the leftovers.

Surprise Rocks
(Printable recipe)

Ingredients

• 2 c. sand
• 2 c. all-purpose flour
• 1 c. coffee grounds (leftover from brewing coffee in a coffee maker)
• 3/4 c. water + possibly 1/4 c. more

Directions

1. Combine the sand, flour, coffee grounds, and 3/4 cup water in a large bowl. Knead, as you would bread dough, until the mixture comes together into a workable dough. Add the remaining 1/4 cup water, a little at at time, if needed.
2. Take a small amount of dough (about the size of a golf ball), flatten it, and form it around your object.*
3. Bake at 250 degrees for about 30 minutes, turning over after the first 10 minutes. Store uncovered.

This recipe covers about 12 small dinosaurs.

*Note:  It's best if the dough is just thick enough to be workable in covering your surprise object, but not too thick.  If you make it thick, it'll take the rocks a long time to bake in the oven or the dough may not dry out enough at all.  For larger objects, you will need a larger amount of dough.  Large surprise rocks may require additional baking time.


Have fun and enjoy!