Primary STEM resources
This page is a list of free (as in no payment required) resources for teaching STEM topics at the primary level (ages 5-11). Some may be under non-free licences.
Science edit
Science Net Links edit
Free lessons from the American Academic for the Advancement of Science. Also has secondary level resources. http://sciencenetlinks.com/lessons/
NASA edit
Public domain educational resources from NASA. https://www.nasa.gov/education/resources
CK-12 science (grades 1-5) edit
Textbooks with questions for grades 1-5: https://www.ck12.org/elementary-science/
Technology edit
CS Unplugged edit
Computer-free computer science activities designed for primary school students from Google and Microsoft. https://csunplugged.org/ CC-by-SA-4.0
Engineering edit
Hacking STEM Library edit
Upper primary (middle school) library of activities from Microsoft Education. https://www.microsoft.com/en-us/education/education-workshop/activity-library.aspx
Mathematics edit
CEMC edit
Free booklets to assist mathematics teachers of Grades 4, 5, 6 from the University of Waterloo. http://www.cemc.uwaterloo.ca/resources/invitations-to-math.html
NRICH - enriching mathematics edit
Activities for enriching maths learning by the University of Cambridge. https://nrich.maths.org/
Also has resources for the pre-school and secondary school students.
mep - Mathematics Enhancement Programme edit
Complete mathematics curriculum for primary aged children. http://www.cimt.org.uk/projects/mepres/primary/index.htm