This is my boat.It can carry at most 43 coins.I think if we want to make the floatage more stronger, the first thing we should think about is the balance ,so my teammates and me designed two cabins to keep it .

Hypothesis:If there are more space of the boat, it can carry more coins.Because the more water you discharge, the greater the buoyancy.

conclusion :the  more water the boat discharges, the more coins it can carry

We did a interesting experiment today about how to make the boat flow the longest time with the most pennies.I think the important things are keep the Drainage volume as much as you can and put the pennies evenly to keep every part having same stress of uniform.The more drainage volume you keep, the more flow force it can have.