Your experiment needs to come down to one variable: one thing that is different. This will be different for every experiment. If there is only one variable that will change, you can measure that change to prove, or disprove your hypothesis. Some kids may feel that if they don't prove their hypothesis, they have failed. That's so far from right, it's not funny. What the science fair project is supposed to teach you is the process of science. In the real world of science, there are thousands more failures than successes. If you can say why the project didn't turn out the way you expected, it is just as valuable as if it turns out the way you wanted.

 

Links  Sites to help you in your project
1. ScienzFair Projects:  What is the Scientific Method & Experimental Science Fair Projects http://members.aol.c om/ScienzFair/tips.htm Hosted at AOL but available to anyone on the Web.  These two articles explain the steps and define the kinds of information to be collected in doing a Science Fair Project.   Each idea listed also includes a link to supporting information Web sites.
2. Cyber-Fair: See the Steps Involved in Doing a Project http://www.i sd77.k12.mn.us/resources/cf/steps.html K-12 Science fair steps, descriptions, tips and guidelines.  Hosted in Minnesota but applicable to all students
3. Science Fair Central: Students Getting Started:  Science Fair HandBook:  Scientific Method:  Project Experimentation http://school.discovery.c om/sciencefaircentral/scifairstudio/handbook/scientificmethod.html#exp erimentation Discovery Channel's Discovery School site description of deciding and stating a good science fair project experimental design for testing your hypothesis
4.  Scientific Methods: Biology4Kids:  Questions and Answers & Experimental Proof http://www .kapili.com/biology4kids/study/method.html Simple clear description of the process of stating a hypothesis (asking a question) and testing a hypothesis (experimenting and observing the results of the experiment).
5. Science Fair Primer:  Designing an Experiment http://www.capecod.n et/~trowan/Design.html Science teacher, Ted Rowan of Falmouth, MA schools writes this primer for K-12 science projects.  Designing an experiment describes how to state an hypothesis which is testable.
Jenna's Diary January 17th When Jenna went to school she talked to Mr. Eisnaugle her science teacher. She told him about how she got her idea with her mom and what she found at the library. Mr. Eisnagule was very impressed. "So what is your hypothesis, Jenna?" "Well Mr. Eisnaugle, from what I have read, I think that grass in dirt that has lots of nutrients will grow the best grass."
"Now you're ready for the next step, Jenna." "I know," she said with enthusiasm, "I have to design my experiment!" "That's right, Jenna. When you get your idea for your experiment ready, come talk to me again." "Okay, Mr. Eisnaugle, I will."
January 21st Jenna got too busy the rest of the week and forgot completely about her science fair project. She was busy going to her brother's basketball game. There was the birthday party for Sarah, her best friend. Too much good stuff going on. On Saturday, her mom asked her about her project. "Oh gee mom, I forgot about it." "Well, you don't want to repeat last year do you?" "No mom, I don't. " "What did Mr. Eisnaugle tell you to do next? "I'm supposed to design my experiment." "Do you need help?" "Let me try to do it myself, mom." "Okay, if you need help, I am here." Jenna went and got her books and magazine articles and piled them on the kitchen counter. She thought for a little bit. Then she began to write:       four flower pots, each one with a different kind of soil       same grass seed       see which grows the best When she was finished, she got her mom to come into the kitchen.
			When she got home that night, Jenna sat down with her mom. "Here's my plan, mom. Mr. Eisnaugle and I talked about it today." Jenna showed her mom her notebook with the revised experiment;
"eight flower pots, each one with a different kind of soil. each set of four needs to be the same size and shape start the second set one week after the first set same grass seed all of the pots need to go in my south bedroom window they get the same amount of water each day see which soil grows the best grass"
"That looks good, Jenna!" her mom said. "Let's go see if we can find what we need." Jenna and her mom went off into the garage. They found six flower pots, pretty much the same shape and size. "I think we can buy two flower pots that will be like these," her mom said. "Sure. We don't have any grass seed either." "We will just have to put that on our list." They went back into the house. "Can we go get the pots and the grass seed now mom?" "No Jenna, but we will sometime tomorrow."
January 23rd On Monday, Jenna talked with Mr. Eisnaugle again. She showed him her idea. "That's pretty good, Jenna," said Mr. Eisnaugle. "There are a couple of things I would add though." "Like what Mr. Eisnaugle?" "Well," he said, "they are only minor additions. You need to have eight flower pots, two sets of four." "Why is that Mr. Eisnaugle? I am only testing four types of soil?" "You need eight in case there is a problem, Jenna. Sometimes things don't go just like you want. If you have eight, you can start four one week, and four the week after so that if something went wrong with any of the first four, your project wouldn't be ruined." "Oh, that's cool!" Jenna said. "I never thought of that." "You need to also make sure each one has the same amount of water each day. You're testing the different kinds of soil right?" "Yes, Mr. Eisnaugle." "That's what I thought. So all the other things that might cause the grass to grow differently need to be the same." "OK." "Another thing, put all of the flower pots in the same window so they all get the same amount of sunlight. If you can, make sure all of the flower pots are the same size. You can use one size with one set, and another with the other if you can't find eight identical pots." "I see," said Jenna.
January 24th
Jenna and her mom went to the store. They found some grass seed and some starter pots that were on sale. These will be very handy because they are all the same shape and size. All together they spent $4.68.
		When they got home, Jenna went outside and dug around the corner of the yard. The soil she found there was of the clay variety. Next she went across the street to the neighbor who had such nice grass. She asked them if she could dig up a pail of soil from there yard. They said sure, and it was good dirt.
When Jenna's dad came home, she asked him if he knew where there was any sandy or gravely soil? He thought for a minute. "I think so, let's get in the truck and look.  "Sure enough, next to Mr. Morrison's house they found a pile of gravel.
Jenna went up to the door and asked if she could have a bucketful for her science fair project. "Sure!" he said, "and good luck."  Jenna filled up a bucket and got back in her dad's truck.  When they got home, Jenna mixed some sand with soil. Now she was ready to go.