Can you build the tallest and strongest tower?

We have:

Made Towers using spaghetti sticks and Marshmallows.

We changed:

The size of the Marshmallows and the length of the uncooked spaghetti sticks.

We thought:

Towers will fall down if structures are not strong enough. 
Square-Based Towers will have the strongest structure. 

Big Marshmallows will be too heavy for the top. Longer spaghetti sticks will give towers the strongest structure.

We found out:

Triangular-Based towers have the strongest structure.  

Big Marshmallows are too heavy for the top of the structure.

Shorter spaghetti sticks provide greater strength than longer spaghetti sticks.