They may not be K'Nex but they are still a "rod and connector set" of sorts!
All kinds of fun can be had with marshmallows and toothpicks! And you can even eat the connectors - Can't say that of K'Nex!
So let your imagination run wild... but please do not try to break the Guinness World Record for the most marshmallows eaten in 1 minute. (Full-size ones.... is 25, achieved by Anthony Falzon (Malta) in Sliema, Malta, on 25 March 2013.)
One afternoon my daughter suggested that we get out the marshmallows and toothpicks and here is the result. She took most of the photos and built everything but the large bridge structure.
I hope that you have as much fun as we did!
Step 1: Gather Your Supplies
You will need lots of mini marshmallows and lots of toothpicks.
It's best to let the marshmallows get a bit stale as they have greater strength and gripping power. I don't have a preference regarding multi-colored or white marshmallows. We had both on hand, but the multi-colored seemed to be a bit more stale, and therefore better building materials.
I prefer round toothpicks to the flat ones; they have greater strength.
Step 2: Basic Building Concepts
Triangles and Squares are your basic building blocks. Triangles are inherently more stable than squares.
Squares tend to lack rigidity, and so we want a cross tie to strengthen it. But unfortunately geometry requires that our hypotenuse be longer than the sides-- and our toothpicks are all the same length.
The solution is to bend our square into a parallelogram. That gives us a nice strong building block that is really two triangles put together.
Step 3: What If I Like Square?
If you like squares or have a particular need for a square structure (and who doesn't?) you can slide an additional marshmallow onto the side and add two cross ties. This makes a really strong building block.
Now you have some basics from where to start. Now go build something really cool!
Step 4: Build in 2D and 3D
You can start building in 2D and then add connections to pull multiple 2D parts together, or you can just 'go for it' and build in 3D from the start. Sometimes during building, such as in the large bridge, things started falling apart and so additional cross ties or braces or just plain more toothpicks and marshmallows had to be added at strategic locations to hold things together.
Experiment and have fun!
Step 5: Expand Your Horizons - Let Your Imagination Run Wild!
No reason to limit your creations to structures. Go ahead and build animals and people -- Whatever you can imagine!