How Big is Big?

Your ice cream is bigger than mine. My car's bigger than yours. I'm big enough to do that by myself. But how big is big? Ms Watson and her class decide to hit the road and find out. How big is the Big Banana or the Big Pineapple? Could the whole class fit inside it? It's not as big as that whale out in the ocean. Or as big as some of the stories the class will tell when they get back home. Everything's a maths problem - and it's a lot of fun.