Every science themed birthday party needs a grand finale! One event that will really stand out in the minds’ of your guests. One activity that they will go home talking about and remember as the highlight of your science themed birthday party. This post will show you how to wow your guests by creating an Exploding Soda Surprise that will impress your guests and conclude your amazing birthday party with a BANG!


2 liter Diet Cokes (one for each participant)

Mint Flavored Mentos (at least one roll for every two participants)

Construction paper (one sheet for each participant)

Scotch tape

Duct tape

Toothpicks (the pointy kind with sharp ends)

Eye protection for each participant

A table and outdoor area that can get messy



Provide an area where the birthday party guests can work together to build their launch tubes. To do so, each guest will need to roll their sheet of construction paper around a pack of Mentos. Instruct the guests to not wrap the paper tightly and allow for the pack of candy to slide out easily.

Use scotch tape to secure the roll of construction paper to keep it from unraveling. Encourage the guests to work together to tape the launchers, and make sure each guests has a chance to use a pack of Mentos to create their launcher.

While the guests are working on creating their launch tubes, an adult will need to set the two liter Diet Cokes (use Diet Coke as it is sugar free and doesn’t cause a sticky mess) up on a table outdoors. The soda can potentially launch dozens of feet into the air so the adult needs to insure the overhead area is clear of obstructions. Place the sodas on the table in a way that will allow room for each guest to stand. Remove the cap from each soda. Tape a six or so inch piece of duct tape to the edge of the table by each bottle. This tape will be used by the adult to secure the launcher to the two liter bottle.

Once the guests have created their launch tubes, have them put on their eye protection and move to where the soda bottles have been setup. Do not allow them to get too close to the soda bottles as they could accidently knock them over. One at a time, the adult should take a launcher from a guest and secure it with the piece of duct tape to the soda bottle. Once the adult has done this for each guest, they will now need to go back and push a toothpick through each launcher. When the guests remove the toothpick, the Mentos will fall into the soda bottle and trigger the eruption.

After the launchers have been secured to the soda bottles and the toothpicks have been inserted, load five to six pieces of Mentos candy into each launcher. Now you are ready to allow the birthday party guests to approach their soda bottle. Have each participant keep both hands on their heads as they approach. The excitement has usually peaked at this point and the guests are getting eager. This excitement can knock a bottle over and trigger an eruption by accident!

Instruct the participants that there will be a countdown that starts at ten. When the countdown reaches the number 3, each guest is to put one hand on the bottle to steady it for the launch. At 2, the participants are to remove their other hand from their head and grasp the toothpick. On 1, the participants are to remove the toothpick and the Mentos will fall into the soda causing the soda to erupt!

The Exploding Soda Surprise is a fabulous activity for any science themed birthday party. Although this activity is very messy, the excitement you will see in the birthday party guests will be worth every bit of cleanup.