Marshmallow toothpick structures are always a hit with kids, and these heart-shaped marshmallows and toothpicks are all you need for this fun STEM / STEAM activity for Valentine’s Day!

Be sure to check out all our Valentine’s Day ideas for kids!

My kids and students have always loved building with marshmallows and toothpicks (and we’ve also created with orange peels and toothpicks)! When I found these heart-shaped marshmallows at the store, I couldn’t wait to let the kids try the same activity, but this time with a Valentine’s Day twist. (This post contains affiliate links.)

Heart Marshmallow Toothpick Structures

Materials for Heart Marshmallow Toothpick Structures

Heart-shaped marshmallows (We found ours at our local Target.)
Toothpicks

We used round toothpicks, but they can be quite sharp. Flat toothpicks might be a better choice if you are doing this activity with younger children or with a large group of children. (Colored toothpicks would be fun too!)

Creating Heart Marshmallow Toothpick Structures

There’s so much to love about this activity! It encourages creativity and problem solving– kids love trying to create all kinds of structures and have to problem solve if they don’t turn out as planned.

I also love how this activity is pretty much adaptable to any age. Many young children find it easier to create flat designs rather than 3-D structures, while older children love building up. Even I had fun creating!

How My Kids Used the Marshmallows and Toothpicks

My preschooler, Theo, started by building some small structures.

Eventually he decided he loved creating super long designs the most. He said they were like railroad tracks!

He was so proud of his completed structure when he was done!

My first grader, Lucy, first wanted to create shapes. We started with some simple plane shapes and then moved onto some 3-D shapes.

Then she decided to build a big house…

…which ended up complete with a roof!

And even though I wouldn’t let the kids eat the marshmallows as they were building (I know- how cruel LOL) , I caught this little guy sneaking a taste!

More Fun Uses

This heart marshmallow and toothpick building activity would be perfect for a Valentine’s Day party. It’s very inexpensive and tons of fun! It would also be a great geometry lesson to do in the classroom as Valentine’s Day approaches!