In Search Of . . . . Real Science
The Student Concept Of What Is Science
When kids take their first science class in school, they think that every lab activity is an
experiment. This notion is far from the truth. I maintain that an experiment is an investigation in
which the experimenter attempts to test a hypothesis. We do lots of other things besides
experiments such as demonstrations, replication exercises, and descriptive science. Descriptive
labs and replications are all too common in textbooks. Descriptive science can be legitimate science
so long as observations are made and relationships are inferred by the student. A major theme of
biology, form and function is often taught this way.
Replication exercises usually short change the student by depriving them of the opportunity of
discovery learning. This not real science. Rather than start by asking students a general question, a
replication lab will follow a thorough textbook discussion of a phenomenon. Diffusion and
osmosis are usually explained before students do the lab. The lab is simply replicated to illustrate
the process or to reinforce understanding. This is tell and show. Students have the answer they
think you want them to know. Where is the scientific thinking?
Real Science Is . . .
Real science for our students is when they are thinking scientifically. What all real scientists do is a
special brand of critical thinking. Like all critical thinking, there must be a purpose for thinking.
That for scientists is generally "I want to know how or why something works in a particular way.
Or what relationship exist between two things?" What distinguishes scientific thinking from other
forms of critical thinking is how we refine our questions and develop the concept we are working
with. What this involves is a hypothesis. A guess about how or why something works in a
particular way. And for those of us who experiment, this involves a test of our hypothesis.
Demonstrations can be effective if they challenge a student's preconceived concept. This can be
accomplished by using an inquiry approach. Start with an observation and follow with a
question. Require students to develop a hypothesis then design an experiment to test it. For
diffusion, set up a molasses cell in water and ask students to hypothesize why the liquid rises in
the vertical tube.
Overcoming the Weakness in the Science Curricula
The weakness in the science curriculum that creates a barrier for students to think clearly and
scientifically is stating the hypothesis. In this forum I will . . .
demonstrate how hypotheses are an essential part of science methodology.
demonstrate formatting hypotheses that will teach students how to focus on the
important parts of a scientific problem and learn to make appropriate predictions and
We have all read and heard that good science teaching emphasizes process skills or higher order
thinking skills. These process skills are implicit in the "scientific method". Science dogma
describes the method as a series of steps such as stating the problem, observing, hypothesizing,
experimenting, collecting data and so on. The one part of the scientific method that is the least
apparent and seldom explained adequately is hypothesizing. Although it is commonly accepted that
students should know the scientific method, few students can get beyond the hypothesis.
Why is this?
I believe that students have difficulty with hypotheses because their books and lessons mention
hypotheses, but almost never really explain or model them. And frequently hypotheses are
confused with theories. A good many teachers use the terms theory and hypothesis
interchangeably. No wonder our students are confused. From the California Science Framework:
"hypothesis--a proposition assumed as a basis for reasoning and oftensubjected to testingfor
its validity." Also from the framework, "theory--an explanation or model based on observation,
experimentation, and reasoning, especially one that has been tested and confirmed as a general
principle helping to explain and predict natural phenomena."
I look at a hypothesis as a proposed relationship to be tested, a concept in need of validation. On
the other hand, a theory seems to be broader. For example Redi tested the hypothesis that maggots
on decaying meat come from flies rather than from the meat. The theory of biogenesis states that
living things come from living things, like produces like. This theory was the outcome of many
experiments and observations including scientists such as Redi, Spallazani, and Pasteur. Students
need guidance in understanding the difference between these two terms.
Why Do Students Need to Know How to Hypothesize?
Biology students need to know how to hypothesize simply because the hypothesis is the core of
experimentation which in turn is the ultimate opportunity to utilize critical thinking as a scientist.
Of course, students need to develop the cognitive skills involved in descriptive biology and the
manipulative skills using laboratory equipment. However, cognitive skills and manipulative skills
alone can not explain the natural world. These important activities do prepare students for the time
when real experiments will be performed. It is during what I call "experimental biology" that
critical thinking skills like hypothesizing, interpreting data, and making inferences can be best
Experimental biology is the ideal place to teach the scientific method. Students can formulate and
test hypotheses. They can manipulate and control variables and observe outcomes of events for
which they don't already know the answer. However, this only works well when the student
recognizes a possible relationship to be tested. Being able to hypothesize allows the student to
focus on the specifics of a relationship. It limits the focus to just two things at a time, the
independent and dependent variables. Furthermore, using some formats, a hypothesis allows
the student to predict what will happen to the dependent variable when the independent variable is
manipulated. It is in this situation we can improve clarity of thinking and utilize the scientific
method to the fullest extent. Furthermore, students who usually miss the target when stating
conclusions can be effectively guided to logical conclusions when conclusions are linked to the
hypothesis. Experimental biology is the perfect place for hypotheses. It is the perfect place to teach
students the process of science, to experience "real" science. To learn how to format effective
hypotheses, click formatting hypotheses.
Sample Lessons for Classroom Use:
About the Author
Linking Conclusions to Hypotheses