The equation: Mini-marshmallows + toothpicks = 2 hours of fun.
6 yr old's creation, top left. 9 yr old's creation, top right. Mine, middle.
The girls and I spent yesterday evening and this afternoon building things with marshmallows and toothpicks. It's important with this work to set expectations - building with marshmallows is a slow and steady process. It can be a little tricky, in a good way, good for little fingers working on fine motor skills. That can be challenging for kids. I tried to set the tone when my structure fell the first time, by laughing and telling it to get back up again! We learned that triangles were strong shapes and that some connections need more support than others.
Consider the snacking potential when purchasing marshmallows so you have extras to munch! Be sure to protect your table with newspaper since the marshmallows get a bit sticky. We let our structures sit overnight. In the morning the marshmallows were harder and held together nicely.
This is a good activity for studying bridges and structures. Find bridge design and construction links at eMINTS from the University of Missouri. A fun triangular marshmallow bridge + another bridge + a tower on Flickr.