Sophia’s third birthday party was a few weeks ago, and I’ve been wanting to share with you all how I created an under-the-sea birthday party theme, complete with bubble balloons, crepe paper seaweed / coral, blue fish, shells, sand and more. It was truly a spectacular day with all kinds of mermaid / under-the-sea party elements that I’m sure she’ll look back at this day with so much fondness!

Under the sea birthday party theme

I wanted the table to be the feature of the party, complete with various under-the-sea elements. Here are the various components of the party and how they were put together!

Crepe paper seaweed / coral

• I simply used long strips of crepe paper / paper streamers. I taped one end to the wall and then twisted the crepe paper and affixed the other side of the strip to the wall with tape. For a seaweed look, use green streamers. For a coral look, use blue or pink (or almost any color) streamers.

Swimming fish

• I found a bag at the Dollar Tree of about 30 pre-cut blue fish shapes. It was in the teacher’s supplies / stationary section. I simply used double-sided tape to adhere the fish to the wall. I tried to place the fish mostly randomly, but also strategically to conceal the tops of the paper streamers.

Seashells

• I scattered shells (also from the Dollar Tree) all over the table. Instead of mixing them homogeneously throughout the table, I grouped them in small groups of 3 or shells and placed those in various spots across the table.

Sand & Candle

• I placed a plain white candle (UNSCENTED) in a bowl full of sand on the table. The sand brings a beach-y vibe to the table.

Bubble Balloons

• After blowing up blue balloons, I taped them to the wall in rows along the edges of the table. The goal is to mimic bubbles under the sea. I used heavy-duty tape to adhere the bottoms of the balloons to the wall, so all that is seen from the front is a smooth, blue balloon.

Hanging jellyfish

• This idea was found from Pinterest and consists of a brightly-colored paper lantern (that is NOT completely stretched open) and several strips of coordinating paper streamers. Together, these elements look like a jellyfish – so cute! Sophia couldn’t wait to play with her jellyfish once the party was over.

Starfish cupcakes

• I made mini cupcakes, frosted them with white frosting and topped them with blue pearlescent candies. I placed them on a starfish platter that I’ve had for years- it’s very similar to this one. It really made the theme come together during the dessert round!

Mermaid outfit

• For the mermaid outfit, Sophia simply wore a big, silvery blue tutu like this one, a plain white tank top and a big beaded necklace like this one. I also made a little shell hairclip for her, simply by hot gluing a hair clip to the back of a seashell. She looked like an adorable little mermaid!

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