This teacher made video does a great job explaining why changing one variable at a time when conducting an experiment is important. It also discusses what the independent and dependent variables are.
Students can either label or put the skeleton together in this online activity. The better they do the higher their score. They can practice it as man times as they want.
A limnic eruption occurs when a poisonous gas gets "belched" out of the bottom of a lake where it was building up pressure. This video discusses 2 famous limnic eruptions and what scientists are doing about them.
This is a great video to show during your unit on adaptations and evolutionary changes. This video demonstrates how sharks have evolved over time to become the top of their food chain. It discusses how their bones and muscles have adapted to become more efficient.
Students will draw and diagram the different phases of the moon depending on how the Earth, Sun, and Moon are positioned relative to one another. Students also get a chance to practice the moon phases and their names. Finally, they get to demonstrate their understanding by drawing their own moon phases.