- 2 stacks of books
 
																								- index cards
 
																								- lots of pennies
 
														
    		    	 
			         
			        
																		- Make 2 equal stacks of books.
 
																								- Lay one index card over the gap between the books.
 
																								- Count the number of pennies you can put on the bridge before it collapses.
 
																								- Now try using a folded card.
 
																 
					 
					 
					How many pennies can your bridge hold?
				
	 
         | 
        
									
		   |