Science Buddies: "Ask an Expert"

I am a parent helping my 4th grader with his first ever science fair project. He chose your Into the Wild Blue Yonder project, but chose to use only one dependent variable (distance rather than distance and accuracy), with independent variable being the mode of launch (throw the model airplane, trigger launch or throw and trigger launch. He is struggling with what his control variable is. Any suggestions as to how I can guide him in that particular area?

So glad you asked! He picked a very fun project for his first time out.

A control is defined as a test where the independent variable is left unchanged to provide a comparison. In this case him throwing the plane with no assistance would be that control.

I have found that a great way to help guide someone in this area is to ask something like...

In this experiment we are using a couple different ways to make the plane go further. But...in which of the 3 ways are we not altering how far it would go on its own? Which way are we NOT using something to make it go further?

Or try--A catapult is a launcher, a slingshot is also a launcher. It looks like we are also going to be using a launcher in this experiment. But, does a launcher make something like a ball go further than it would if we threw it? (use a nerf gun launching a projectile versus throwing the projectile or the slingshot example again if need be)(Yes). Ok. Well, a control requires something we can compare against without assistance. In this experiment which of the 3 ways is assistance making it go further not happening?

You could also try using a video to help perhaps? https://www.youtube.com/watch?v=x2606GQmDqY

Hope this helps. Please reach out again if he is still stuck and you need more ideas!

Elizabeth

Thank you so very much! That was incredibly helpful!