Inquiry-Based Activities for Masses & Springs

For Grades 9-12, this homework assignment lets students explore how the mass of an object is determined using spring balances. Next they use the spring balance to determine the mass of an unknown object, and then find the gravity on Planet X.
http://phet.colorado.edu/en/contributions/view/2817

This is an excellent and truly inquiry style investigation. My students thoroughly enjoyed learning about simple harmonic motion with this resource.
My students thoroughly enjoyed learning about simple harmonic motion with this resource.