This pirate science is perfect for your preschool pirate theme! We loved making these “exploding” treasure chests during many years of preschool summer camps.
You’ll find free printable pirate number cards at the bottom of this post. Add them to your pirate science activity so little pirates can count all of their treasure.
Related: Pirate Sensory Bottle
It was a great sensory experience as the solid, freezing cold chests turned to mush and exposed the treasures hidden within.
Full disclosure, there were no real explosions (although I’m sure you already knew that). Lots and lots of fizzing, of course.
However, the kids insisted on naming this activity “Exploding Treasure Chests,” so I ran with it.
Fizzing Treasure Chests for Pirate Science Fun
To make the treasure chests, I used the recipe from our Icy, Fizzing Letters ABC learning experiment.
You can adjust the additions based on what works best for you, of course!
Pirate Science Experiment Ingredients
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- Baking soda
- Water
- Jell-O powder (optional)
- Pennies or other coins
- Craft gems
- Glitter (optional)
- Don’t forget to grab the free printable pirate numbers at the bottom of this post!
“Exploding” Treasure Chests Pirate Science Video
Here’s a video that shows how to make the fizzing treasure chests!
I’ve written out the directions after the video.
How to Make the Fizzing Treasure Chests
Over the years, my son and I have perfected the recipe for these pirate science treasure chests — 3 parts baking soda, 1 part water, and Jell-O powder as desired.
This particular mix ensures the solution freezes solid and comes out of the ice cube trays in the desired shape.
Related: Ocean Slime Recipe for Kids
I like to add the Jell-O powder for color and scent. You don’t need to add it if you’d rather not.
For many years, I just used plain ol’ rectangular ice cube trays to create the “treasure chests”.
Related: Children’s Books About Pirates
Recently, though, I discovered these awesome treasure chest molds.
I think they add a nice touch, but they definitely aren’t necessary.
After you mix up a batch of the icy and fizzing solution, it’s time to fill the ice cube trays. Fill them halfway.
Once that’s done, add little “treasures”. I’ve used pennies, beads, craft gems, and googly eyes. Just add what you’d prefer.
Related: Messy Science Experiments
Next, fill the ice cube trays the rest of the way. You can add some glitter if you want to (’cause everything’s better with glitter). But the glitter is optional.
Then into the freezer! I let the treasure chests freeze overnight, and they popped out of the trays easily the next morning.
Playing with the Fizzing Treasure Chests
Put the frozen pirate chests out on trays or in bins. Place squeeze bottles filled with vinegar for the kids to use. Add some spoons or eye droppers if you’d like to.
We’ve almost always made this pirate science experiment for preschool summer camps. So when it was time for our pirate fun, I placed some plastic tubs outside. I placed a few frozen treasure chests in each of the bins, then set out spoons and condiment bottles.
Related: Frozen Fairy Tale Science for Preschoolers
Some vinegar went into the condiment bottles, and in a few segmented trays. This way, all of the kiddos could access the experiment.
I told them it was their job, as pirates, to find the treasures hidden in the frozen chests. Then I let the children go at it!
Related: Gold Slime
The condiment bottles were squeezed, and the vinegar was spooned, onto the treasure chests.
The kiddos LOVED when the treasure chests “exploded”, and some really got into squeezing the partially thawed cubes with their hands.
Related: Fun Science Activities with Foaming Names
There were a variety of exclamations throughout this whole process:
- “It’s exploding! They really DO explode!”
- “Hey, smell this, Miss Mary Catherine! It smells yummy! How’d you do that?!”
- “It’s so squishy now, but it’s still cooooold.”
- “Look! I found treasure! I found treasure!”
- “Okay, we need more treasure chests. Really, we need more!”
Most of the children were engaged the entire time we were outside.
Honestly, the kids wanted our pirate science activity to go on for longer, but we had to get ready to go home!
Related: Sensory Pirate Activities
We rinsed the treasure off with some water, and the kids will take it home at the end of the week. I was really happy with how this pirate-themed activity went!
The children were having fun, they were engaged, they were being pirate scientists, and many of them asked to do it again.
If you loved these, be sure to check out Plato to Playdough’s pirate themed playdough kit!
Preschool Pirate Lesson Plans
Save time and get right to the pirate-y fun with done-for-you lesson plans from Preschool Teacher 101. The preschool pirate-themed lesson plans have printable lesson plans for a week, as well as explanations for the activities (for whole group, small group, and center time), book suggestions, and related printables.
Get your pirate lesson plans here
Also available on Teachers Pay Teachers
Free Printable Pirate Number Cards
These pirate number cards are perfect paired with the fizzing pirate science fun! They’re available to members of Fun-A-Day’s free email community.
If you’re already a member, enter your email in the form below to have the cards sent to your inbox.
If you’re not a member yet, that’s okay! You can enter your information in the form below to join us. Then you’ll get the number cards as a welcome gift.
You can also access the form in a new tab if you’d prefer.
Originally written on July 10, 2013.
Wow, Mary Catherine, this looks like so much fun! I love pirates & treasure themes and combining that with your fizzing ice just takes it to the next level. So cool!!
Thanks, Ann!! I had originally tried frozen vinegar with Jell-O, but it just doesn’t freeze right. So we moved onto the fizzing/exploding treasure chests! We had way too much fun with it, and even the kids who’d already explored the fizzy letters LOVED this variation! 🙂
So awesome! Going to find a way to make these for my nephew and niece next time I visit!
Thanks, Jenn! I would love to hear how it goes when your niece and nephew visit! It’s always fun to hear about other people’s experiments!! 🙂
AMAZING!!!!!!!!!!! I love, love, love it!
Thanks so much, Asia!! It turned out even better than I thought it would! 🙂
SO FUN! This is exactly how we made our MAGIC Treasure ICE, only without jello. That is a great addition. Great minds 😉
Isn’t that crazy, Crystal?? I didn’t see your Magic Treasure Ice until just now (via your link)! The exploding treasure chests were a natural progression of the Icy, Fizzing Letters we explored last month — just a pirate-y version. 🙂 I guess because your girls and my son (and students) just love science activities, there were a few crossovers. Great minds and fun kiddos!! 🙂
Absolutely, it is! I even had the idea to make MAGIC letters before seeing yours. Great mind do in fact think alike =D Again, I LOVE the Jello addition!
Thanks, Crystal!! 🙂
This is just the neatest idea!!! I can not wait to try this with Lucy and Theo! You come up with the coolest stuff!
Aww, thanks Chelsey! 🙂 I cannot wait to hear how Lucy likes them! Engineer has already asked if we can do them again, so I envision more Jell-O usage in the future!!
WOW does this look like fun – never seen anything like it! Hope to try it!
Thanks so much, Anna!!! Please let me know how it goes if you’re able to try it out. I appreciate the kind words. 🙂
OMG what an awesome idea! My daughter is very into pirates right now and she would LOVE this. Thanks so much for sharing with us.
Thanks for hosting We Made That every week, Tracey. I love checking out the new ideas people share there. I am so glad you like the exploding treasure chests! I was so happy how this turned out! 🙂 Let me know if your daughter tries it out. And I have more pirate fun coming soon.
This may be my favorite Fun-A-Day idea yet! How FUN!
Thanks so much Rachael! It’s apparently my son’s favorite too! Of course, he says that about almost everything we do. So I bet the next experiment is going to be his favorite. 🙂
Oh wow, Mary Catherine!! This looks fantastic! Look at how engaged they are! I’m totally adding this to our fall line up of activities!
Thanks so much, Jackie! The kiddos were indeed engaged the entire time! In fact, we actually had to tell them to stop and clean up so we could get them ready to go home. I’m sure they would have continued playing with the “jewels” in the icy blue water! 🙂 Ooooh, and if you and the kids try this out, PLEASE let me know how it goes!!
This is the most fun and creative idea EVER!!!! I love it! This would be so much fun at a pirate themed kids birthday party. PINNED! 🙂
Aww, Blayne, you are too sweet! I am so happy with how it turned out too! I do think kids would like this at a pirate party. If you have one, I would love to know how it goes. 🙂 Thanks for the pin too!!
oh so cool Mary Catherine! I love your stuff. Have to use this one! Pinning & Sharing!
Thank you, Sarah! I really appreciate your kind words, as well as the pin and the share. 🙂 Let me know if you do this activity. It’s always so fun to hear how other kids enjoy our activities!!
My kids loved the rocks we made out of just baking soda paste (they dry really hard); will have to try it will jello sometime! Thanks for sharing at Mom’s Library!
Featured you on Mom’s Library this week!
Thanks for the feature, Ashley! 🙂
We’ve just done a pirate themed week at home, really wish I’d seen these beforehand – what a great idea!! It looks like so so much fun!
Great idea! My kids love anything that involves action (fizzing is perfect).
Thanks so much!!! 🙂
I think my boys would love having a go at this. Thanks for linking it up to our Parenting Pin-it Party.
Jut adding to all the other comments here, awesome fun idea!
Thank you, I appreciate the kind words!! We definitely had a LOT of fun with it.
My first grader would LOVE these. My 10th grader is taking chemistry, and the little guy wants to “blow things up too”.
Love it, Meg!! That’s how the kids described it, too — using words like “exploding” and “blowing up”. If you trying it with your first grader, let me know how it goes! 🙂
Too awesome! I LOVE this idea. Will be trying it as soon as Dex is old enough to handle the small pieces. I’m sure he’ll have ruined enough necklaces by then that we’ll have all the treasure we need.
Great way to look at the broken necklaces, Gemma! We used bits and bobs like that too. The kids definitely had a blast with it, so I know we’ll be doing it again. Thanks for popping by! 🙂
This is just cool! I am featuring your post tomorrow on Share It Saturday!
Can I just say that I Love this idea! This would go great with any pirate themed lesson or activity for a birthday party. I could see why the children had so much fun! This is on my activity list now! Thanks!!!
Thanks for the kind words, Kay!! We seriously loved it too! Next time, I’m going to plan it when we have even more time to play. The kids got into some pretend play once all the treasure had been found, and I bet they would’ve liked a little longer with that.
I’m going to make them for my 4 kids and the neighboring kids….except put a little twist to it. We are going to fill water guns with vinegar and make it into a game. They are very excited…I’ll have to keep you posted.
Love the twist of water guns! Please do let me know how it goes — I really enjoy hearing how activities go over with other kiddos. Thanks, Aimee!
I love this idea! My school has a PBIS theme that I have tied into pirates. I have been looking for a fun open house gift to give. This just might be it! I also have a teaching pirates board on Pinterest:-)
I’m so glad you like it, Erin! Let me know how it goes if you try it out. 🙂
They are fantastic, what an amazing idea. Thanks so much for joining our challenge this month. xx
So excited I was able to join in! 🙂
Love this! We have yet to freeze baking soda. We’ve only done frozen vinegar so far.
Love it! Will they melt like standard ice cubes or more slowly because of the jell-o and baking soda?
Thanks Melody! We loved it too, and I can’t wait to try it again soon! They melted slower than regular ice cubes because of all the extra ingredients. It made the cold and fizzy fun last longer! 🙂
This is really really cool!
Do you need the jello? If not I could make these tomorrow….. 🙂
No, you don’t need it — I just like to use it to color and scent the “explosions”! 🙂 Let me know how it goes!
This looks like great fun! I’ m trying it with my grands and then at summer school! thank you! Paula
I am planning a pirate program at the library and I am curious about the recipe for exploding treasure chest. How much of the jello powder should I use? Is the recipe referring to using an entire box?
Let me know how it goes! We just did these again at summer camp and they were a blast. I tend to make a batch with 3 cups baking soda, 1 cup water, and 1 small packet of Jell-O powder.
Thanks for sharing! I just popped a batch of these in the freezer, my kids will love it!
Glad to hear that! Thanks!
I LOVED this activity and I would really like to make it with my kids! I just have a question, did any chaos happen when they were getting the treasures out? I mean as a mess, I’m just wondering if I should take this activity to the backyard or if the classroom would be ok.
We have always done this one outside, as it tends to be a summer activity with summer camps. So yes it gets a bit messy! 🙂 But I’ve done things like this inside too — just made sure to put a tarp down and explained the rules of where the activity was supposed to be. I hope that helps.
Love this activity can’t wait to try it out!
Thanks, Sophie! Let me know how it goes. 🙂
Hog much baking soda and water? I dom’t know how much 2 parts and 1 part is?
Hi Ann! For example, 2 cups of baking soda and 1 cup of water. It just depends on how much you’re making at a time. I hope that helps!