A) Be a rocket scientist-build your own water-powered rocket

Materials
1. 2 squeezy washing-up liquid bottles
2. Strong scissors
3. A bicycle pump or foot pump with an adapter for blowing up footballs
4. A launch pad made from a sheet of plywood or cardboard leant against something

Steps
1. Take the nozzles of the bottles and wash everything. Leave them to dry.
2. Cut the top and bottom off one bottle. Keep the top piece, with its nozzle.

3. Cut the rest of the bottle up its side and flatten it out to make a sheet of plastic.

4. Cut out three fins from the sheet like this.

5. Stick them on to the other bottle like this.

6. When the fins are stuck on, tape the top of the cut bottle onto the bottom of the other bottle to make a nose cone.

7. Half-fill the bottle with water and replace the nozzle. Keep the cap on the nozzle unit you are ready for take-off.

8. To launch your rocket, take the cap off the bottom nozzle, push the adapter in, turn the rocket upside down and put it on the launch pad. Attach the pump to the adapter and pump very hard! Watch your rocket shoot up!

B). Which way will it go?

Materials
1. A straight drinking straw
2. 2 ping-pong balls
3. 1 yard (3 feet) of ribbon or string
4. 2 balloons
5. 2 8-1/2 X 11 sheets of light-weight paper

Steps
1. Blow up both of the balloons and tie the ends off. Tie one end of the ribbon or string to each balloon.
2. Hang the balloons so that they are about 2 inches (5cm) apart. Blow hard between the two balloons. What happens?
3. Next, hold a piece of paper in each hand. Place them in front of your face and hold the two pieces of paper a few inches apart. Blow hard between the two pieces of paper. What happens?
4. Last, place the two ping-pong balls on a flat surface near the edge. Place them about 1/2 inch apart from one another. Stoop down so that you can place the straw between but just in front of the ping-pong balls. Blow very hard through the straw. What happens? Which way do the balls move? Closer or farther apart from one another?

Science explanation
Bernoulli's principle states that when there is an increase in velocity, or air speed, there is a decrease in pressure. The decrease in pressure acts like a small vacuum, sucking the two objects together. The balloons, the papers, and the ping-pong balls all moved closer together and not farther apart as many people would think.

Materials
1. 2 pieces of cardboard 20 X 30 inches
2. Other size cardboard pieces

Step
1. On a windy day, hold a piece of cardboard so that the wind blows against the flat side. You can feel the large force of drag.
2. Next hold the cardboard with the edge facing the wind. In which case is the drag greatest? Do you see any connection between area and drag?
3. Now tilt the board and feel the lift.
4. Then experiment with different sizes of cardboard. You can also fold a piece of cardboard into different shapes and experiment until they find a shape that resembles and airplane (a shape that seems to offer the least resistance to the wind).

Science explanation
Aerodynamics is the study of the forces acting on an object due to air, or some other fluid, moving past it. These forces act upon airplanes, sailboats, and other objects moving through the air and affect the motion of those objects.
Lift enables an airplane, or other object, to climb into the air and remain aloft during flight. For example, an object held flat against a stream of air is pushed backward. However, if the object is rotated forward toward the ground, the air can now push it up as well as back.

D).Wind Tunnel

Materials
1. 8 long wrapping paper tubes
2. Safety scissors
3. A fan or blow dryer
4. 6-12 inches of string for each model you test
5. Duct tape
6. Long pencils or sticks
7. Model airplanes, action figure or Styrofoam shapes

Step
1. Take two of the wrapping paper tubes. Tape them together so that they make one longer tube. Do the same thing for the other six tubes.
2. Stack the tubes together with two tubes across (making two stories). Secure with two long strips of duct tape.
3. Cut out shapes from the Styrofoam. Some should have aerodynamic shapes like an airplane wing and others should be nonaerodynamic (such as a brick shape).
4. Next, turn on the blow dryer and place it in front of the wind tunnel. Tape or secure a plane or shape on the end of a string behind the wind tunnel. Hold it in the airstream behind the wind tunnel.
5. Does the wind current create a lift? (If you try this with a model airplane you can adjust the elevators on the tail assembly which control where the air-plane will climb or dive.) What is the position of the elevators in a nose dive? Watch how the air currents affect the lift, turning, rolling, and dive of a plane or shape.

Science explanation
A wind tunnel is used by scientists to test model airplanes that have the same shape as actual airplanes. Using the wind tunnel gives the scientists information about how a certain plane would respond in flight.

E). Friction

Materials
1. 4 pieces of wood
2. Dishwasher soap
3. 4 marbles
4. 2 pieces of extra heavy aluminum foil; large enough to completely wrap two of the wood blocks

Step
1. Take two of the pieces of wood. Place one on top of the other and lay a hand on the top piece and try to move it. Try and move it by rubbing one piece against the other or using a circular motion. The friction is strong.

2. Place a few drops of dishwasher liquid soap between the two pieces of wood and see how well the top piece moves after the lubrication has been applied. Try this using a circular motion. (Be careful when you rub the two pieces together; if you place too much liquid soap between the pieces it can get a bit messy.) What happens?

3. Now wrap one of the dry blocks completely in the heavy-duty aluminum foil. Have the ends of the foil meet on the back side of the block. Do the same foe the second block. If you do not have heavy-duty aluminum foil you can use a lighter weight foil (but it tends to tear).

4. Place one of the aluminum foil blocks on top of the other aluminum foil block. Now repeat the above experiment. Lay a hand on the top piece and try to move it. Try and move it by rubbing one piece against the other or using a circular motion. Can you move the block? How does this feel in comparison to the wood block?

5. Now, unwrap one of the aluminum foil covered blocks or use the dry side of one of the wood blocks. Place the four marbles in the palm of one hand. Cup your hand a little bit but keep your hand straight to keep the balls in your hand. Rub the block over the balls. What happens? Does the wood block roll on top of the balls? How does that feel in comparison to the other experiments you did with the blocks of wood?

Science explanation
We can reduce friction in machines by lubrication. Oil is put into the machine, where it coats surfaces that rub and makes them slippery. All surfaces have tiny projections that catch against each other as they rub. Without lubrication, there would be great friction, slowing and overheating the machine. The oil film separates the two surfaces so that their small rough spots do not catch.
Lubrication is not the only way to reduce friction in machines. Rolling is another way. Placing small steel balls or cylinders between two moving surfaces allows one surface to roll over the ground on wheels. The balls or cylinders do not rub against the surfaces as they roll, so very little friction occurs.

F). Rocket balloon

Materials
1. Long balloon
2. Straight drinking straw
3. 12 feet of string or fishing line
4. Clear plastic tape
5. Two chairs, any height

Steps
1. Thread the string through the straw.
2. Tie the string between two chairs approximately 12 feet apart.
3. Blow up the balloon.
4. While holding the balloon shut with one hand, secure the balloon with tape to the straw lengthwise as shown below.
5. Release the balloon from one end of the string. Observe what happens. (The balloon and straw are propelled to the end of the string.)

Science explanation
Newton's Third Law of Motion states that for every action there is an opposite and equal reaction. The balloon and straw shot up the line when you let go. In this case, the air escaping out the back of the balloon is the action. The opposite reaction propels the balloon forward along the string.