General Chat / Note Card Tower Challenge

So in AP Physics, our teacher gave us the Tower Challenge. In a nutshell, we have to build a tower of note cards 11" high that will support a 5lbs brick for 5 seconds. Now heres the hard part...
-All folds must be good creases (no rolling into cylinders)
-Cannot cut or slit the cards
-Permitted to use staples and unlimited supply of cards but...

Simulated money system:
-Each staple and card = $1
-Must spend less than $45 to get an A+, less than 50 for an A, and so on...

I've tried multiple ways of doing this. All have failed. When I do come up with something good, I end up using too many cards, putting me in the D-F range. So my question is, do any of you guys have any ideas/tips/advice to help me out here? Im getting kinda frustrated and I know some of you are smart people

Thanks in advance,
TW

EDIT: Forgot to add that each fold costs a hypothetical $1 too...

Why not try a base of cards 6 wide and 8 length ways. Cards on average are 2 inches(Maybe more not to sure), So you only need 6 platforms and as you go up reduce it by one wide and one length ways and hopefully by the time you get to the top platform it should be 4 cards 2 wide and 2 length ways and the 5lbs should hold, Hopefully If i had the materials here i would try it myself ... Try google or something. Good luck mate Edit: Fold the ones at very top at the top of the card and in the fold place a card standing up as a support. I think if i had everything i would be able to do it but i dont

I don't know how many cards you'll need for this but you could try this:
grab 3 cards and make a triangle with them supporting on each other.
but make it so that a card can be placed on all 3 of them.
so a triangle from top view.
stack a card on it so you have used 4 cards.
this per level, that way you can make it about 10 levels high. That'll be high enough but I don't know if it's strong enough..

^yeah try triangles. 1 staple per card, and just stack up. a 3" wide card would only need 4 stacked, so $8/column. that gives you six columns of them to go for an A, but you'll have to get creative when stacking. that's how i'd tackle it at least.