Kidsites 

http://www.kidsites.com/sites-edu/science.htm

Links to kid-friendly site on a variety of topics

Khan Academy

Real Science 4 Kids (Not program of Studies)

Kiwico Crates

(Not program of Studies)

CPAWS

https://cpaws.org/

PBS Learning Media

https://www.pbslearningmedia.org/

Lots of different activities and videos

We Are Teachers

https://www.weareteachers.com/virtual-lab-activities/

Virtual lab activities

Wonderopolis

https://wonderopolis.org/wonders?category=science

How It Works 

https://www.neok12.com/How-It-Works.htm

Educational videos and games