[teacherman]

Can anyone recommend a good website or ipad app about the elements geared towards 4th graders?

[aggie'swife]

I'm not quite sure exactly what you are looking for, but this periodic table has pictures and examples.
http://periodictable.com/Elements/045/index.html

There are many others that have the oxidation, valence electrons, etc, but that would be too much information for your 4th graders.

Chem kids has a periodic table with info about the families...
http://www.chem4kids.com/files/elem_intro.html

I also came across this which includes some lesson plans, starters, periodic table link, etc. It is for 5th, but you could adapt it.

http://betterlesson.com/lesson/36938...-table-day-6-7

[ginadoo]

You're in luck! I just saw this today on ed ted. Hope it is good for 4th.

http://ed.ted.com/search?utf8=%E2%9C...periodic+table