Luis M., Grade 4, IL
An electric can-opener is an example of a wedge, a screw, a lever and a wheel with axle. The wedge is on the cutter. The screw holds the can-opener together. The wheel and axle is holding the cutter on. The lever is the handle. The cutter cuts the can by itself. We just need to push the lever, instead of turning a handle a lot of times.
Brandon A. - Grade 7, SC
A highway on-ramp is an example of an inclined plane. A highway-on ramp allows cars to go from one level of road to another level of road. Cars can't go up steps so the ramp makes it easier. You get a shortcut but a lot of nature is gone.
Brittany Ann K., Grade 4, IL
A door knob is an example of a wheel with axle. The wheel is the circle that connects the handles together. The axle is the part that goes through the door and lets the knob turn. This simple machine makes things easier to open and close. The trade-off is you don't have to pull or push and you can just turn the handle.
Erica, Grade 3, IL
A window-blind cord is an example of a pulley. When you pull the string it goes up. It's easier to pull than to lift. The short string needs to be pulled many more times.
Jessica & Michelle, Grade 3, NJ
An ice-cream scooper is an example of a wheel with axle. When you pull the handle the scooper turns and pushes out the ice cream. It makes the job easier because for scooping
ice cream you need power, but with an ice cream scooper you don't need much power. If there were no ice cream scooper you would have to scoop ice cream with a spoon.