I’m a bit last minute with Valentine’s Day this year. My 10-year-old is currently making a card next to me while I plan some easy activities for us tomorrow.

These Valentine STEM challenges are designed to be very easy and use only basic materials.

If you’re looking for something a bit more involved, check out my full collection of Valentine’s Day science experiments. The magic colour changing potions are my favourite!

Send a Valentine’s Message

The idea behind this Valentine’s Day STEM challenge is to create a delivery mechanism for a Valentine’s message. This could be a paper plane, paper spinner, zip line or any other creation that flies!

I’ve created a paper spinner template and straw rocket template to make this activity as easy as possible!

Valentine paper spinner template

Print the template, cut out the spinners, write a message and then watch the spinner fly through the air!

Valentine straw rockets

Write a message on the plane and send a unique Valentine’s Day message to a friend!

Write a Secret Message

Write a secret message with lemon or lime juice.

Lemon or lime juice makes a great DIY invisible ink for writing secret messages. Just pop the paper in the oven to reveal the message.

Blow up a Balloon Heart

This simple science activity uses an alka seltzer or baking soda and vinegar to blow up a balloon heart.

This Valentine’s Day scratch card coding activity from Code Wizards is great fun, too.

Last Updated on February 6, 2024 by Emma Vanstone