This guide will give you everything you need to know to throw a fabulously simple ocean-themed outdoor birthday party for kids. Grab the water balloons, and get ready to have a splashy birthday bash!
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My three-year-old little guy just turned FOUR last week! He is a strong-willed, big dreamer who loves to build and invent new creations. He is a little obsessed with fighting bad guys, but he’s also the biggest snuggle-bug I know. He is stubborn as all get-out, but I’m pretty sure that’s going to be a good thing as he gets older. And he’s got just about the best cheesy smile ever.
He’s also incredibly indecisive. For the months leading up to his birthday, he would come up with a new idea every two minutes…Star Wars, Legos, dinosaurs…and so on.
My favorite one was when he told me, “Mom, I’m going to have a box party.”
“What’s that?” I asked.
“A box party,” he replied matter-of-factly. “And everyone is going to wear a box costume.”
I was kind of curious to see that one come to fruition, but–once again–he changed his mind (and probably for the best). By this point, I had pretty much given up on him ever choosing a theme. I figured that a few days before the party I would tell him he had to make a decision and stick to it. But he surprised me.
A few weeks before his birthday, he announced that he wanted an ocean-themed party. Okay, I thought, we can work with that. His birthday is in July, so “oceans” fit perfectly with doing an outdoor water party. Thankfully, he stuck with the ocean theme from then on!
So I got to work planning!
Keeping it simple
As always, I had to stop myself from going overboard. There are SO many fun ideas out there, but life has been CRAZY lately for us, so I’m trying to simplify where I can.
I always ask myself, “Will doing this/buying this make the party better for MY CHILD?”
This helps me focus on finding low-effort, big-bang-for-your-buck party ideas to make the day special without staying up all night pulling it together.
I have to say, this party was my most successful as far as keeping things simple. And, you know what? I think we ALL enjoyed the day a little more because of it. I only went crazy for about 15 minutes when I realized the kiddie pool had a hole in it, the baby woke up and needed to eat, and we couldn’t find the birthday boy’s swimsuit anywhere…all 15 minutes before the party was supposed to start.
But, my husband is amazing (and very patient), we rallied, and everything turned out fine.
Here’s the party!
Our ocean-themed birthday party
Invitations
I designed the invitations in Photoshop Elements using free graphics. I have to say, I was really happy with how they turned out!If you want to use my design, you can download a template FREE by clicking on the image above or just click here to download your invitation.
- Once you click, the template should open in your browser as a JPEG file.
- Right click, choose “Save image as” and save it to your desktop (or another location of your choice).
- You should be able to open this in any editing program you want to use: Photoshop, Canva (a great free tool), even Paint.
It’s printable up to 5×7 inches, perfect for printing on your home printer or sending to Costco for quick invites. Just add the personalized info for your party in the blue space under the sea, and you’re good to go. In case you want to use the same fonts I did, I used Luna for his name and Ostrich Sans Heavy for all the other text.
If you use them, let me know!
Decorations
I always try to keep decorations simple for kid parties. Our party was happening in our back yard, and I didn’t want the water games to leave me with a bunch of soggy crepe paper to clean up, so I didn’t do a lot out back. I’ve had a plastic beach mural (similar here) for about a decade, so I pulled it out and put it on the back fence for fun.
Otherwise, I just put up a table for food that I covered with a blue plastic tablecloth and some blue place mats I already had.
I found this adorable idea for making seaweed out of crepe paper, so I used that to decorate the front door and the gate leading to the backyard. I also made this simple sign to direct guests to the back so I didn’t have to man the front door during the party.
Download your free printable door sign here.
Food
Our party was from 3-5 PM, so we just had snack foods, rather than a full meal. My favorite food creation was my shark watermelon. Super low-effort (It took me about 15 minutes to cut up the whole thing), but a big kid-pleaser. Here’s the watermelon shark tutorial I used.I also put out some Goldfish crackers and popcorn in a party tray (dollar store), and I made a big pitcher of lemonade to drink.
Half-way through the party, I also served Otter Pops. It was great motivation to get the kids to clean up all the broken bits of water balloon after our water fight.
If you want to expand your menu, here are a few more simple ideas:
- Swedish Fish candies
- Banana dolphins
- Octopus veggie platter
- Blue jello & sea foam cups
The Cake
Making birthday cakes is one of my favorite creative outlets. I think it’s fun to sit down with the soon-to-be birthday boy and browse Pinterest for ideas, then make our favorite ideas come to life.
This ocean cake was SUPER easy to do, and the birthday boy was thrilled with his edible ocean. I started out with a white cake (box mix). I added food coloring to the separate layers to give it an ombre effect on the inside (which I forgot to take a picture of…oops). Here’s an inspiration ombre cake to give you an idea of the look.
Once the cake was baked (and frozen, because I think they are easier to frost when frozen…and it allows me to do the baking on a different day), I made a basic buttercream frosting. I made a double recipe of this “quick and almost-professional buttercream icing” recipe. I separated the batch into four bowls, and made 3 varying shades of blue as well as one bright green for the seaweed. Here’s a video tutorial for creating an ombre effect with icing.
I used a leaf tip for making some seaweed, and a round tip to make some simple sea shells (I took some leftover blue frosting, added some red coloring to make it purple and piped some little swirly shells). I finished off the cake by making a graham cracker crumb island, topped with the main character’s from my son’s favorite show: Octonauts. It would be easy to replace the Octonauts characters with characters from Finding Nemo, The Little Mermaid, or generic sea creatures like a whale, dolphin or shark. The sky is the limit!
Activities
An ocean party is the perfect theme for a simple outdoor water party in the heat of summer. We had the following free-play activities set up:
- kiddie pool
- water table
- slip ‘n slide
- sand box
- squirt guns/refill station
We already had all these items, so it was NO added cost to us (except for $4 for a 12 pack of squirt guns at Walmart). Hooray for parties where you can use what you have. If you don’t already have some of these things, consider making one of them your birthday gift to your child.
Below are some more fun water play ideas. Some of these we did, some I’ve done at other water parties in the past, and some just look too fun not to share.
Do keep in mind that a water party doesn’t need to be over scheduled. I had planned on doing more structured games and activities, but the kids really just wanted free play time, so I obliged.
Great activities for a kids’ water party:
- bubble station
- water balloon games
- “The Shark Bit My Cup” relay race
- water obstacle course
- “Roll 6 and splash!” game
- wet sponge toss
- sponge bombs
P.S. – What did we do in the days before they had these awesome mass-fill water balloons??? Seriously, I don’t care that they are more expensive. They are SO worth saving my fingers and my time. Until my kids are old enough to fill their own water balloons, this is the only kind I’m buying.
PIÑATA
The piñata is a key part of birthday parties for my kids. I’m not sure how it became their expectation, and I’m kind of wishing I hadn’t set the precedent that we always do them. But, it is their birthday, after all, so I suppose I can be a little indulgent. This jellyfish piñata was made with the traditional paper-mache-over-a-balloon method. Once I had the basic shape, I filled it, attached a cardboard circle for the bottom, and covered it with crepe paper (I describe how I decorate my piñatas in this post). I added streamers and curly ribbon to be the tentacles, glued on a face (made from simple construction paper) and called it good! I thought he turned out kind of adorable.
Favors
Our party favors were simple. I let each child pick a water gun to take home, and they got to take home their bag of piñata loot as well. Easy peasy!
AND THAT’S A WRAP!
It was a low-key party, and proof that you don’t have to spend a ton of money to create a memorable party for your kiddos. Use what you have, buy a few inexpensive things to supplement, and let the kids PLAY. Sometimes, the best ideas really are the simple ones.
Happy splashing!
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This is a great decorating job! I especially love the cake and the watermelon. I will have to borrow the watermelon for a grown up function! Thanks!
The watermelon was really so simple! I’m glad you’ll be able to use it!
That Octonauts cake is the cutest!! I wish my kids had summer birthdays!!
Thanks, Kim!
What a cute party theme! I wish my grandson was born during the summer! It will be an effort in futility if we have a splash party in December! Haha. Anyway, I will still recommend this theme to my cousins. I know I have some little nephews and nieces who were born in June and July.
Maybe you could have an indoor un-splash party??? Bring the kiddie pool inside and fill it with ball pit balls. Have everyone wear their swimsuits….hmm, now I want to do this!
So, so cute!! I especially love the watermelon shark!!
Thanks, Patricia! I thought he was kinda cute. 🙂
The piñata would be the highlight of the party! This is such a nice party theme. Kids born in the summer are lucky to have so many party theme options.
So many adorable ideas!!!! I love all the sweet decor, and that cake 🙂
I was so pleased with the cake, and it took me under an hour to decorate…all during the baby’s morning nap. Hooray!
Lots of super duper cute ideas for planning a fun summer party! Pinning these for later
Thanks, Misty. We had a great time!
My son is also born in July and he turns 4 this year! He is obsessed with sea creatures and everything ocean. When I asked what type of party he wanted he didn’t hesitate in saying sea animals. I had no idea where to start (Because i like to start early) but i stumbled across your site and it has been really helpful. thank you!
I’m so glad, Ciara! I hope your son has a great birthday!