Our kids always had scinece fair projects and I bought a great series of childrens books, say about 6 to 8 books that were full of science projects suitable for a science fair. heck out your local library in the childrens department for science books.
I remember two that my son did. The first one was to build a Hydrometer to measure the density of liquids. You can google Measuring Density of Liquids or Hydrometer and find some good stuff.
Another one I remember was, i can't think fo the name I think it is distallation, but is was basically about distilling. We borrowed a bunson burner from the high school, I bought this glass tube that was in a coil and we heated up sometthing, water perhaps, the steam went up into the coil and then then came out again as water.
The hydrometer one was really pretty fun, we built, he built I guided, our own hydrometer and we measured the density of all kinds of liquids, we even made salt water and oh, I ran out of liquids so I even let him measure the density of beer.
The distillation one was also pretty cool but I don't think it will make it through the rules.
One other idea, in the old days when making your poster board, we bought stick on letters. Nowdays the kids jsut print it up on computer make the font large and attache the visuals that are computer generated. Believe me this saved lots of time preparing the poster board.
Good luck I think science fairs are neat!
