This is a good site to meet the objectives of description and measurement of weight using a student interactive activity that asks them to compute their weight if they were on other planets. Good graphics, easy to follow instructions for teacher and student. This site requires Java script. New A well organized interactive site with java models of atoms that students can control and observe how changing the properties affects the results. Over a dozen different interactive models for students.
Some models offer controls for friction, gravity and more.
A good source enabling students to gather information on atoms, molecules, elements, compounds, and mixtures. This site contains information about elements in the Periodic Table. Students can take a quiz at the end. This site contains directions and notes for a science demonstration that models the structure of an atom and matter. A good source enabling students to gather information on atoms, molecules, elements, compounds, and mixtures.