This place has some great science and history ideas for the third grade. These could be edited to work with a higher or lower grade. Third Grade Thinkers: Science: Earth Cycles Need to make sure its accurate to prevent misconceptions!
Recording the Earth's rotation with shadows - a great way to give kids a concrete understanding of how the Earth's rotation makes the sun appear to move across our sky. Also a great activity for learning preschoolers about time!
Create your own model to show how the Earth orbits the Sun while the moon travels around the Earth. Great manipulative to help explain the concept. Identify and describe characteristics of the sun, Earth and moon as familiar objects in the solar system.
This human sundial shadow science experiment is a hands-on way for kids to learn how shadows are made and measure the earth's rotation. Contains questions to ask during and after the experiment. Shadow Science Outdoor STEM Science experiments for kids