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34 Under the Sea Party Ideas

Under The Sea Party Ideas

Updated on: Sep 20, 2024

Are you looking for an excuse to escape to the ocean for a much needed break but need to plan your child’s party? If you're looking for party themes, plan an Under the Sea themed party! An Under the Sea party is the perfect theme for the spring or summer months, keeping the kids entertained, and making you feel like you're relaxing with your toes in the sand.

In order to have the most perfect Under the Sea party, you must have great decorations, party favors, a delicious menu, games and entertainment, party supplies, and memorable invitations. In this article, I cover all of these essentials and more. So, after reviewing this article and picking your favorites, you will be ready to throw the most relaxing, memorable Under the Sea party to celebrate your child's accomplishments and help you stay on budget.

Under the Sea Party Ideas: Decorations

1. Jellyfish Hanging Lanterns

These fun hanging decorations are a perfect addition to your Under the Sea party. With just a paper lantern, curling ribbon, streamers, googly eyes, and string, you can create a fun jellyfish creature that will make you feel like you are underwater.

2. Balloons & Streamers

Available at your local grocery or supply store, these party decorations are a staple at any party. Getting blue and white balloons creates the look of bubbles, while green streamers make it look like you have seaweed hanging straight from your ceiling. You can also find customized balloons online if you don't have the time to make your own.

3. Netting

What's an Under the Sea themed party without fishnet? Many fishermen use these nets to help them catch creatures under the water. Use this to decorate a table, or any flat surface; this will add an underwater vibe that you didn’t know you needed.

4. Seashells

Use seashells as table decor, or just placed randomly throughout the party, to make it seem like you are on the ocean floor. If you are looking to spice it up, make some homemade candles with them to use as a centerpiece or even bury them in the sandbox for a fun treasure hunt!

5. Mermaid Backdrop

Did the party even happen if you don't have pictures to prove it? Create a fun mermaid scale backdrop that your guests will never forget. These supplies can be found at your local party supply store and are guaranteed to add to your Under the Sea theme. You can also get props for a little extra fun!

6. Lawn Signs

Welcome your guest with a lawn sign. They can be a cute decoration as well as a way to help your guests know they're at the right party.

Under the Sea Party Ideas: Favors

7. Beach buckets

Fill a beach bucket with fun trinkets such as a shovel, trowel, seashells, and candy to send home with party guests. Leaving with a bucket full of sand and fun will make them feel like they just left the beach.

8. Shark Craft

This craft is perfect for kids to make during the party, and to take home as their very own party favor. Fill up an empty water bottle with water, blue food dye, glycerine, sparkles, and a toy shark, and it will look like the kids have caught their very own shark to take home!

9. Under the Sea Snow Globe Aquarium

Similar to the shark craft, this fun party favor can be made in a mason jar. Fill the jar with water, glycerine, blue food dye, sparkles, and plastic sea creatures such as starfish, fish, octopus, and more to create an aquarium that the kids can use as decoration.

10. Stickers

Stickers can be really fun for kids. You can buy stickers where the kids will create their own, or just buy some cute and funny ones.

11. Water Growing Sea Animals

These work like magic. Give them to the kids and let them be in awe as the little sea animals grow in the water.

Under the Sea Party Ideas: Food Ideas

13. Rock candy coral

Coral is found all over the ocean floor and what better way to recreate it than with candy! This yummy treat is the perfect addition to any party, but making it blue, green, or white makes it seem like it came straight from Under the Sea.

14. Shark Watermelon Fruit Bowl

This is a perfect addition to a summer Under the Sea party. It can be used as a table centerpiece. Kids are able to reach directly into the shark's vicious jaws to get a healthy, refreshing snack.

15. Drink of the Ocean

This fun drink will not only keep your guests hydrated, but also make the kids think that they are drinking the ocean! Perfect for the summertime, fill a large jar beverage server with water, clear soda, or lemonade, then add in blue food dye to create an ocean-like blue color. Placing it on an old crate, or decorating it with a fishnet, makes it seem like this “ocean water” was scooped right out of the ocean itself.

16. Oyster cookies

This cute dessert option is perfect for a kid's party. Place two cookies together, with frosting in the center, to create an oyster look. Place a candy pearl in the center to complete the adorable cookie.

17. Cake

Whether it is a birthday party or just a summer day of fun, a cake or dessert is always a must-have. There are many ways you can decorate your cake or cupcakes to resemble the Under the Sea theme using a variety of colors and cake fondant.

18. Cake Topper

Finish off the cake with a topper. This will really tie the cake altogether. If you are doing cupcakes, then you can find toppers for those as well.

19. Ocean Blue Lemonade Popsicles

Popsicles are a staple during the summer months and can easily be customized to whatever color or flavor you would like! To make these popsicles Under the Sea themed, just use lemonade as the popsicle base, add blue food coloring, and Swedish fish. Freeze the popsicles in their molds, and after a few hours, your popsicles are done! Looking like the ocean water with candy fish swimming around, kids will not be able to resist these treats.

Under the Sea Party Ideas: Games and Entertainment

20. Treasure Hunt

Pretend like you are pirates going to sea to find treasure. For the treasure, you can put chocolate coins or any other type of candy. Hide clues around the area and have your guests go find them.

21. Ocean Slime

What better way to keep the kids entertained than with a homemade slime table! With only a few simple ingredients, it is an easy craft that all ages will enjoy. Add in a few plastic sea animals and blue coloring to make it look like the animals are swimming in the ocean.

22. Sandbox

Make it seem like you are on the beach with this sandbox. It is excellent entertainment and also Under the Sea themed, so it will have kids occupied for hours. Use it to build sandcastles or hide seashells under the sand for a treasure hunt. This sandbox is the perfect addition to your party.

23. Under the Sea Photo Booth

This excellent idea will help your guests remember your Under the Sea party forever. Set up an underwater scene with jellyfish hanging lanterns, seashells, starfish, streamers that act as seaweed, and other fun props to make the pictures look as if the kids were swimming underwater! You can also get a backdrop for some extra fun.

24. Swimming

What better way to host an Under the Sea party than with a pool! Having the kids dive to the bottom for as many seashells as they can collect will not only keep them cool during the summer but entertained for hours. Don't have a pool? A simple blow-up pool will do just fine. Telling the kids that the water came straight from the ocean will keep them swimming forever.

Under the Sea Party Ideas: Supplies

25. Dinnerware

What's a party without plates and utensils? Add to the theme of the party by providing iridescent paper plates that resemble mermaid scales or cups and utensils in blue and green colors. These Under the Sea themed plates and napkins would be a perfect addition.

26. Seating

Seating is a staple at any party to allow guests to sit and enjoy themselves. You may even get lucky and be able to acquire some colored chairs that match your overall Under the Sea theme. If you can't find colored chairs, get some beach chairs.

27. Treat Stand

Bring waves to the party with this cute treat stand. You can put appetizers or desserts like the oyster cookies and cupcakes!

28. Tablecloth

Get an Under the Sea themed tablecloth. This is cute and also an easy way to keep your table clean.

29. Straws

Go the extra mile and get Under the Sea themed straws. They can be used as party favors and will be fun for everyone!

Under the Sea Party Ideas: Invitations

30. Mermaid invitations

What's more of a warm welcome than one from a mermaid herself? This set of mermaid invitations is a perfect way to kick off your Under the Sea celebration. With a fun, colorful background and lines to enter in the party information, these invitations may be perfect for you.

31. Seashell invitations

This simple, yet effective party invitation is a great way to invite your guests to your Under the Sea-themed party. Written on durable cover stock, this is a high-quality invitation set that will be sure to get you an RSVP.

32. Bubbles invitations

This fun, cute, Under the Sea party invitation, is a simple and perfect invitation option for your upcoming party!

33. Surfs Up

It's time to catch a wave! Invite your guest with using a beach invitation.

34. Fish Invitation

Get a little more creative. Get these fish-shaped invitations and invite your guest for some Under the Sea fun!

Under The Sea Party Ideas: Conclusion

After reading this informative article, I hope you are able to make an informed decision on what to bring to your Under the Sea party; whether it's ideas in the realm of decorations, party favors, menu ideas, games and entertainment, supplies, or invitations. An Under the Sea party can be a great choice for a kid's birthday party or just for a fun day in the sun.

Written by Haley McKee; Contributor: Daren Phu

Daren Phu

Aurora University

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Haley McKee

Sonoma State University

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