Complete Requirements 1-3.
An experiment is a "fair test" to compare possible explanations. Draw a picture of a fair test that shows what you need to do to test a fertilizer's effects on plant growth.
Visit a museum, a college, a laboratory, an observatory, a zoo, an aquarium, or other facility that employs scientists. Prepare three questions ahead of time, and talk to a scientist about his or her work.
Complete any four of the following:
An experiment is a "fair test" to compare possible explanations. Draw a picture of a fair test that shows what you need to do to test a fertilizer's effects on plant growth.
Imagine that you’re a medical researcher who wants to test three new medicines to see which one helps people who have a cold feel better. If you gave a sick person all three medicines and he got well, how would you know which medicine worked? You wouldn’t!
But what if you started with three sick people and gave each one a different medicine? Then you would know which medicine (or medicines) worked.
When a scientist asks a question, he or she comes up with a fair test to answer that question. This is called an experiment. An experiment is designed to rule out possible explanations and, as much as possible, test only a single explanation.
In an experiment, like above, scientists look at three things. We will call it C-M-S or Change-Measure-Same. To help you remember, just say “Cows Mooing Softly!”
C - Change is the Independent Variable - Which medicine each person takes.
M - Measure is the Dependent Variable - What are the measuring or looking for - Do they get well?
S - Same is the Control (or Control Variable) - What they will keep the same - They are all sick
Activity: Draw a picture of an experiment to test fertilizers. First, think about what independent variables, controls, and dependent variables your experiment would use.
Measuring the Impact of Fertilizer
What would you add to the list of controls?
What are some other ways to measure if the fertilizer made a difference?
It is hard to imagine how far apart things are in space. On sci-fi shows people zip from place to place. But, even in our own “cosmic neighborhood,” our solar system, distances are vast. Using toilet paper we will build a scale model of the solar system to help visualize how far apart the planets really are.
You will need about 40 feet of uninterrupted space - a long hallway or a driveway (on a calm day).
Materials:
☐ Roll of Toilet Paper, ☐ Paper ☐ Pencils/ Crayons/ Markers
Optional: ☐ objects to weight down TP if you are outside on a breezy day
☐ transparent tape (for repairs)
Directions:
Make a card for each planet and the sun. For each card include:
Name: Write the planet’s name (or the Sun)
Fun fact: even though every other identified body in space has a scientific name or designation our sun does not. It is just the ‘Sun’ (capitalized) - sometimes it is referred to as Sol or Solis (Latin), but those are not official either. It does have its own mathematical symbol.
Picture: Draw a picture
KM: List the distance from the sun in kilometers (metric is the preferred unit of science)
TP: List the number of TP squares
Start with the sun and roll out toilet paper squares according to the chart below.
Place your cards as you go along. You can round partial numbers up or down to whole squares
Materials:
☐ 1 - 9v battery (will use again for experiment in ‘Engineer’ adventure),
☐ 12 inch piece of Aluminum and/ or Copper Tape, divided
☐ 3 - 3mm LED Batteries (Red, Yellow, and Green),
☐ Scissors,
☐ Tape/ Washi Tape,
☐ Paper/ Cardstock,
☐ Ruler,
☐ 2 jumbo craft sticks,
☐ Push pin,
☐ 3 rubber bands,
☐ pencil,
☐ 2 - 3v coin batteries
NOTE: Before you begin, read the instructions and look at the pictures so you understand the set up. Once you tape down the pieces they will be fixed.
We included both aluminum and copper tape in our C.U.B.S. While experimenting I preferred the aluminum, however many have had great luck with copper. We can say without a doubt everything listed below will work. I am not an engineer and if I can light up a LED bulb you can too! We can also say if it does not work the first time try, try again. Most likely your connections are not correct somewhere along the way.
In a series circuit, the electricity goes through each of the output devices in turn.
Directions:
First, snip four ½ inch x the width of the tape strips of aluminum tape. Save the rest for the next circuit (parallel).
2. We are making an ‘L’ shape. Take a piece of tape and peel back the paper backing. Stick one piece completely to the paper to form the upright part of the ‘L’ shape.
3. Use another piece to make the base of the ‘L’ - leave a small gap between the upright and the base.
4. Take the remaining two pieces and tape them down to form a square with the ‘L’ pieces - but DO NOT CONNECT the corners.
5. Tape the three LED bulbs to the three open corners. Save the ‘L’ base and upright gap for your battery (it should be more narrow and even than the others).
Make sure all your positive ends are pointing the same way or the circuit will not work. Tip: The longer wire on the LED is the positive. You can mark it on your paper to make it easier to remember.
6. Add the 9v battery to close the circuit. If you accidentally put the battery the wrong way just turn it around.
7. All your lights should be lit! If it is not working troubleshoot your connections and the direction of your positive and negatives
In a parallel circuit, the electricity follows separate paths through each output device.
Directions:
Mark one of the craft sticks as shown in the first picture. The two dots will be where you feed the LED bulb wires through, the plus and minus indicate which side should be positive and which side should be negative.
Using two separate holes will help your wires stay separate.
Using a push pin, carefully poke holes in the six dots.
Flip the stick over and insert the pin from that side as well, to make sure the hole has gone all the way through.
Gently, in twisting motions, wiggle the pin all the way through the six holes so that they are large enough for the wires. If the stick cracks it is okay you can tape it together, if necessary.
5. Guide the wires through the holes. If you mix them up it is okay as long as all the positives are on one side and all the negatives are on the other you can flip the batteries around later and they will all light up together.
Also, make sure your lights are in the correct order - red on top, yellow in the middle, green on the bottom. You can test your bulbs by sliding a battery between the positive and negative wires. Then press to make sure they are touching. It should light up. If not, flip your battery over and try again.
6. Trim the remaining pieces of aluminum tape to slightly shorter than the craft stick. If it’s a bit long or wide it’s okay you can wrap it around the stick.
7. Place a craft stick on the tape and mark the width, trim and repeat for the other stick.
8. Lay the narrow piece alongside the stick with the LEDs in it. Mark about ½inch past the bottom of the LEDs. And, note how wide the LEDs are. You are going to cut a notch in the strip so that only one half of the strip is touching the LED wires, but the bottom half is full width. Look at the picture to guide you.
9. Once cut, pull the backing off the strip and adhere the thin part behind one half of the LED wires and press the full width section down the rest of the length of the craft stick.
10. Bend the wires in so that they touch the aluminum.
11. Take the other pieces of craft stick-width aluminum tape and notch it the opposite way. Adhere it to the blank craft stick. When you lay it on top of the other stick the aluminum strip should be on the side with the unbent wires.
12. Bend those wires in too.
13. Assemble the Stop Light - Sandwich the wires aluminum sides facing each other.
14. Secure with three rubber bands - one beneath each light.
15. Slide two 3v coin batteries, facing the same direction, into the lower part of the stick and press down. Lights!
If your lights do not come on try flipping the batteries and checking the connections. If only some of the lights come on you probably switched the positive and negative when you pulled them through the stick.