I came accross this great collection of physical science lessons for elementary students.  The activities are really well planned and easy to follow.  I hope you can use them.

• Battery Life
• Engineering Toothpaste
• Fish Tank Optics
• Gliders
• The Hidden Jewels of Geometry
• Ice Energy & Making Ice Cream
• Making a Shoe-Box Guitar
• Making a Water Lens
• Maple-Seed Helicopters
• Materials That Absorb Solar Energy
• NASA Robots
• Paper Clip Sailing
• Paper Rockets
• Pizza Box Solar Oven
• Positively Paper
• Rocket Pinwheel
• A Solar Heat Experiment
• Sounds Like Science - Bottle Organ
• Sounds Like Science - Drums
• Sounds Like Science - Guitars
• Sounds Like Science - Jamboree
• Sounds Like Science - Kazoos
• Water Energy
• Where’s the Air?

• Air Pressure
• Altitude Tracking
• Antacid Tablet Race
• Balloon Staging - Rocket Staging
• Balloons - Why Are They Stretchy?
• Battery Life
• Bicycles - How Do a Bike and Its Rider Stay Up?
• Car Engines
• Colored Shadows - Using Lights to Mix Colors
• Domed Stadiums - What Keeps Inflated Stadiums Up?
• Engineering Toothpaste
• Finger Boomerangs
• Fish Tank Optics
• Flying Tube
• Flying Wing
• Four-Wing Paper Boomerang
• Glass Blowing
• Gliders
• Guess What?! (a lesson about atoms)
• The Hidden Jewels of Geometry
• Hollywood Stunts
• How Can I Control the Soccer Ball?
• How Do Clocks Keep Time?
• Ice Energy & Making Ice Cream
• In-Line Skating - Do In-Line Skates Really Go Faster than Roller Skates?
• Lemon Power
• Liquid Bottle Rocket
• Liquid Nitrogen Fun!
• Making Paper Airplane Gliders
• Making a Steam-Powered "Rocket Boat"
• Making a Straw Woodwind
• Making a Water Lens
• Maple-Seed Helicopters
• Match Stick Rocket
• Materials That Absorb Solar Energy
• McEagle Styrofoam Glider
• Musical Tube
• NASA Robots
• Newton Car
• Paper Clip Sailing
• Paper Rockets
• Peanut Power
• Pencil Rockets
• Ping Pong Ball Curves
• Pizza Box Solar Oven
• Playing With Polymers
• Positively Paper
• Robots
• Rocket Car
• Rocket Pinwheel
• Science Safari: Energy Resources
• Scuba Diving
• Sewer Science - Where Does Sewage Go?
• Soda Pop Can Hero Engine
• A Solar Heat Experiment
• Sounds Like Science - Bottle Organ
• Sounds Like Science - Drums
• Sounds Like Science - Guitars
• Sounds Like Science - Jamboree
• Sounds Like Science - Kazoos
• Splitting Water - H2O Hydrolysis
• Using Bubbles to Learn about Light Interference
• Water Energy
• Where's the Air?
• Wooden Helicopter