Hands-on is definitely the order of the day as students inquire into and investigate the magnificent world of machines. Student notes explain the six simple machines (inclined plane, wedge, screw, lever, wheel and axle, pulley). Related teacher demonstrations and simple-to-do student activities and discovery sheets accompany these core lessons. Student notes are included for possible enrichment lessons dealing with gears, hydraulics, and how a car works. More involved, optional assignments stress creative and critical thinking in addition to building a degree of flexibility into the unit. This Physical Science lesson provides a teacher and student section with a variety of reading passages, activities, crossword, word search, and answer key to create a well-rounded lesson plan.