Matter, forces, mass, gravity and weight

This is an introduction to forces for KS2 or KS3. It goes into more detail than perhaps is required, but it offers some key concepts that are often neglected and that I feel it is important to communicate. Despite the additional level of detail, I have found the material to be accessible to KS2 and KS3 students. The lessons require some basic practical activities.
The topics covered are: Matter, Forces (general), Mass, Gravity and Weight.
The resources include presentations and worksheets. I do not claim that the resources are complete and exhaustive; feel free to make use of them as you please, and I shall continue to modify them. Feedback is welcome.