Pumpkin Science

I put out a new science experiment yesterday entitled "Pumpkin Sink or Float". I have this work set up at a permanent "station" so that the children can just sit down and perform the activity. I leave work out like this on rare occasions, maybe if it's only going to be out for a few days and I want the children to see it and work with it, or if there are too many parts involved in the work for the child to carry from the shelf to a table.

On the table, I have a tray, an apron, a large bowl, a sponge, an orange colored pencil, and a stack of experiment papers in a plastic folder. The experiment paper has an area for predictions (a space for a picture and a line for the word "sink" or "float") and a similar area for conclusions. After putting on the apron and filling in the paper, the child carries the bowl to the sink. There is a black line drawn on the bowl to show the water's surface line.

Now for the fun part...the child carries the bowl back to the tray and places the pumpkin gently into the water. It typically bobs up and down for a few moments and then settles on the surface of the water. It fools them all! Finally, U.P., my afternoon kindergartner, commented "We keep guessing that the pumpkin will sink. And it floats every time. Will the answer ever change?" That is the point of the experiment. Are there any factors that change the composition of the pumpkin so that it will sink? I'm curious to see if any children will alter the pumpkin in any way before putting it in the bowl. I'll keep you posted on any progress of the pumpkin experiment!