Well, wouldn't you know the boat was large enough to hold all the cranberries I had and still float! Ok, so plan B.
He then made the prediction that the bigger piece would not sink when the same number of cranberries were placed on it and that it would take more to sink it. He was correct and it took just over twice as many to sink the larger piece of foil.
Of course all of this floating/sinking led to a discussion about how cranberries are grown and harvested. Over this summer on our road trip with Nana, we visited Cape Cod and were able to see cranberry bogs. However, it wasn't harvest time, so they weren't flooded yet. We looked at pictures from this website.
This would probably make a fun water play bin for kids as well. I think I'll let Sassyfras and Juiciness play with it when they get up from their naps.