```Sliding AlongL'Ouverture Perkins            Carter Elementary School                               5740 S. Michigan Ave.                               Chicago IL  60647                               (312) 535-0860 OBJECTIVES:Compare and contrast movement of objects on smooth and rough surfaces.

State Goal #1 - The concepts and basic vocabulary of biological, physical                  and environmental sciences and their application to life                  and work in contemporary technological society.              General knowledge /skill related to State Goal #1 How two or more things interact and the effect each has on the other.Third grade objective
Demonstrate the relationship of complex machines and friction.

MATERIALS NEEDED:1 wooden board 3 feet by 2 feet (approx) 1 metal tray or board1 matchbox1 piece of stone1 piece of wood1 eraser1 ice cube2 bowl1 rubber ball1 tennis ball1 jarsoap and waterreal money2 pieces of sandpapervaseline or margarineoil and greasebicycle tirecar tire1 small flat bottleSTRATEGY:                        anticipatory set

To begin this lesson on the exploration of friction you can introduce
this little "science trick":

1.  Take out some money and put it inside of a jar.
2.  Screw on the lid of the jar as hard as you can.
3.  Choose a student and wash their hands thoroughly with soap and
water
4.  Do not dry their hands; keep them soapy.
5.  Challenge the student to get the money out of the jar.
*6.  Student should not be able to open the jar if hands are slippery.

Experiment #1

Investigate Friction

Materials - Wooden board, matchbox, piece of wood, eraser and an ice cube1.   Arrange the objects in a line along the edge of the wooden board. 2.   Slowly raise the board until the objects begin to move.3.   Which object moved first?4.   Repeat the experiment using the metal tray.5.   Do the objects move more easily.....or less easily?6.   Do you have to to lift the metal tray higher than the wooden board before     the objects will move?7.   Which surface has the lowest friction?                             Experiment #2

Friction in Water

Materials - bowl, water, tennis ball and rubber ball 1.   Get a smooth rubber ball and a tennis ball.2.   Put a little water in the bowl.3.   Spin each ball in the bowl.4.   Which one moves more easily?                                           Experiment #3                                      Reducing Friction with WaterMaterials - metal tray, soapy water, flat small bottle, books for incline1.   Prop up the tray on the books to make a slope.2.   Wet one side of the tray and try sliding the bottle down each side in turn.3.   Now rub soap on the wet side and slide the bottle down again.  4.   On which surface does the bottle slide most easily?                        Performance Assessment#1 Materials - Two pieces of sandpaper, oil and/or grease1.  Student will take two pieces of sandpaper.2.  Student will rub the two pieces of sandpaper3.  Student will be asked to reduce the friction of the two pieces of sandpaper.Student should realize that using grease or oil between the two pieces of sandpaper will reduce the friction.                      Performance Assessment #2 Materials - matchbox, stone, wood, eraser, ice cube, wooden slide, metal               slide, soapy wet slide,

1.  Student will choose object and slide that have the least amount of friction
between the two surfaces from larger choice of objects and different slides.
2.  Student will choose object and slide that have the greatest amount of
friction between the two surfaces from larger choice of objects and
different slides.
3.  Student will time both experiments and determine the range of difference.

Reference - 175 Science Experiments, Brenda Walpole, Random House; 1988```