What are good science projects for a second grader and a fourth grader?

[Riprorin]

My kids have a science fair in a couple of weeks.

Any suggestions?

 

[Heisenberg]

X-ray diffraction.
Sorry, I don't know. We never had any science fairs when I was a kid.

 

[Ikonomi]

Your forth grader can make a Bose-Einstein condensate, and your second grader can build an autonomous bipedal robot. They will both get an A+++++++++++.

 

[azazyel]

I actually have a good one for you. Have them grown bean plants. To do this you just get some 2 litter bottles cut them in half then fill the bottom with soil add the seeds then put the top back on. It makes a little greenhouse. Then for the science get some colored plastic and rap it around then bottle. You can have your kids guess if one color helps the plant grown In reality you will be able to see which colors of the spectrum that plants find most helpful in growing.

 

[Pliablemoose]

I've been dying to do this with one of my kids: Lifter

Barring this potentially dangerous project, you might browse around in here: http://www.ipl.org/div/kidspace/projectguide/

 

[azazyel]

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