simple machine book2

Hello everyone!  Welcome to the final day of simple machines.  This time, we got complex physics machines.  For example,  we use a simple triangle shaped pusher to lift heavy weight easier.  In real life, that is how we use tools to save our energy and time.  The main differences between human and animal is that we know how to use tools to make our life easier.  At the end of the class, we finished book2 and accomplished our goal.  Next week, we are going back to build complex lego toy.  Hope you guys have enjoyed.