2nd Grade:

Soils, Pebbles, Sand
http://www.fossweb.com/modulesK-2/PebblesSandandSilt/activities/findearthmaterials.html

TLW sort pictures of living and non-living things.
http://www.firstschoolyears.com/science/resources/games/ourselves/living/living.htm

Living and Nonliving Things
http://www.bbc.co.uk/schools/scienceclips/ages/5_6/ourselves.shtml

8 living things
http://www.bbc.co.uk/schools/scienceclips/ages/6_7/plants_animals_env.shtml

3rd Grade

Part World Tracks
http://www.engineeringinteract.org/resources/parkworldplot.htm

Make Tracks
http://sideshow.questacon.edu.au/maketracks.html

Push and Pull
http://www.bbc.co.uk/schools/scienceclips/ages/5_6/pushes_pulls_fs.shtml