Using only these supplies, which question can Cole investigate with an experiment?
Does white sandwich bread grow visible mold in fewer days if the bread is stored inside or outside the refrigerator? Does white sandwich bread grow visible mold in fewer days if the bread is stored in a paper bag or in a plastic bag? Does white or whole wheat sandwich bread grow visible mold in fewer days?
Cole starts to make a sandwich, but he sees mold on the bread! He wonders what factors affect how mold grows on bread. So, he decides to design an experiment. He has the following supplies available:
two loaves of white sandwich bread
a small plastic bag
a large plastic bag
a refrigerator
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment.
Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment?
First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available.
Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick.
So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!