Warm-up discussion with the process
1. From what you remember, what are the steps of the scientific method?
2. What is the purpose of the scientific method?
3. When was the last time you used the scientific method?
Letís talk about question #2 and #3 first.
There are lots of different reasons for using the scientific method.† Many of the uses of the process donít even have anything to do with school.† Iíll even bet that, for most of the students in class, the last time they used the scientific method it wasnít even related to school or homework or anything like that.† It was probably when they went to purchase something of valueóa car for example.†
They saw a car that they liked, did some research on it, tested it out and came to some sort of conclusion.† This is a great example of the scientific process.
Question number 1.
It seems like every book I read or every teacher I have describes the scientific method slightly different from the next one.† I donít think Iíve had two science teachers teach it with the exact same order or terminology.†
For this class, I have condensed many of the possibilities and different terminologies into a simple acronym OHECC (oh heck).† It simplifies the scientific process and makes it easier to remember the most important steps.†
Check and see if these steps fit into the example of buying a new car.
Q:† What is the purpose of experimentation?
A: †The main purpose of experimentation is to test a hypothesis.
††††††††††† There are many different types of experiments out there.† In most branches of science, the most commonly used is the controlled experiment.† These are usually done in the laboratory.†
The parts of a controlled experiment:
1. Control Group
a. All variables remain constant throughout the experiment.
2. Experimental Group
a. Variables are manipulated with this group during the experiment in order to see the effect of each desired variable.
There are a couple of different types of variables in a controlled experiment.† Let us look at what we might find in the experimental group.† The two different types of variables are:
1.† Independent Variable
a.† The variable or thing that is changed or manipulated in the experiment (the amount of steroid if we wanted to test the effect of steroid on chipmonk growth).
b.† This could be defined as the one thing in the experimental group that is different from the control group.
3. Dependent Variable
a. This is the effect or the result of the independent variable on the experimental group (growth, size, mass or whatever you are measuring on the experimental group).
b. This variable ďdependsĒ upon the independent variable
Observations and Descriptions
There are many ways to describe things in the science world.† In a controlled experiment (or any kind of experiment) there are two specific types of observations or descriptions:
††††††††††††††††††††††† This has to do with the quantities related to the thing being described or observed.† It always involves numbers and some sort of measurement.
††††††††††††††††††††††† This has to do with the quality of the thing being described or observed.† It involves descriptions of physical and other characteristics that donít require numbers or measurements.† Color, taste, smell, texture, hardness and ingredients are all examples of qualitative measurements.