Here a some great oniline resources for science lessons designed for at home learning and science fair experiments.
Scholastic Learn at Home - lessons
Mystery Science - lessons
Science buddies- ideas for science fair projects and experiments
Virtual Fieldtrips to Explore
Raft.net has projects using household items. Check them out!
Check out Twig Science at home - free trial. Lessons and activities. There is a digital packet you can download for each grade and you can follow that, or you can search by grade level and pick the topics you are interested in.