Performance Objective: Given a chronological list of well-known scientific theories, students will accurately identify at least 4 of the 9 theories provided as theories that they (students) have studied in middle school science classes. Given sample statements and journal prompts, students will correctly define scientific theory, scientific law, and scientific fact and identify scientific theories, laws, and facts, getting all three definitions correct and correctly identifying at least 5 of 6 given examples.
Content: “Scientific Fact, Law, and Theory” journal prompt:
“In science the following words have the following definitions, and these often differ from the ways these words are used outside of science.
Fact = a repeated, observable occurrence (data)
Law = a description of something that regularly happens in a specific set of circumstances
Theory = an explanation of how something works that is based on scientific facts and has been repeatedly confirmed by the scientific community
Answer the following questions in your journal.
What is a scientific fact that we have established in our class?
Can a scientific law become a theory? Why or why not?
What is required for a scientific theory to change?”
Beginning of Unit Instructions for the "How Scientific Is it?" Activity:
In groups, complete letters A-F of the "How Scientific" activity with the following instructions projected on the board.
How Scientific Is It?
How do we decide that something is scientific versus something that is unscientific?
On your handout and just below, you will find six knowledge claim statements.
1) Read each of the knowledge claim statements with your group.
2) Discuss and agree on an order to the claims from that which you deem least to that which you deem most scientific.
3) Place the claims on the spectrum from less scientific to more scientific.
Less scientific <——————————————————> More scientific
4) Justification: Be ready to explain to others the justification you used for your placement of each item on the spectrum.
Knowledge Claim Statements (project all of this on the whiteboard)
A. All living things are composed of one or more cells. We know this because every living thing examined to date has been found to be composed of one or more cells.
B. If you break a mirror, you will have seven years of bad luck.
C. The Earth is flat. Anybody can see that!
D. Taking Vitamin C prevents the common cold. Linus Pauling, the Nobel laureate who discovered the structure of Vitamin C, says it does.
E. Humans have a soul. I believe this because it says so in the Bible. The soul is what separates us from animals.
F. The rate of acceleration of all falling objects on Earth is constant. Two spheres of identical diameter and volume are dropped from the top of a building; one is made of steel, the other made of a plastic polymer. They both will accelerate at the same rate (32 ft/s2) and hit the ground at the same time.
Less scientific <———————————————————> More scientific
“Scientific Theories” journal prompt:
“Here's a timeline of some of most significant scientific theories.
1540's - Heliocentrism Theory (Earth revolves around Sun)
1777 - Oxygen Theory of Combustion and Respiration
1808 - Atomic Theory
1839 - Cell Theory
1859 - Evolution Theory
1902 - Chromosome Theory
1915 - Gravitational Theory
1920's - Quantum Theory
1927 - Big Bang Theory
1960's - Plate Tectonics Theory
What trend(s) do you notice in the dates?
Which theories did you study in 7th grade, and which have you studied in 8th grade?
What does "scientific theory" mean?”
The definition of theory that is often used in other contexts, including English language arts and other middle school classes, is like what “hypothesis” means in science, and is really nothing like what theory means in science.
Examples from 7th grade science, last semester in 8th grade science, and just last week:
Gravitational Theory (Objects with mass bend the space-time continuum to move toward each other)
Law of Gravity (The attractive force between objects is related to their masses and distance between them)
Fact: A pencil dropped near Earth's surface accelerates at 9.8 meters per second squared
Plate Tectonics Theory (Earth's surface and it's features and geological events are a result of the movement of the plates that make up Earth's crust)
Law of Superposition (In non-disrupted areas, the deeper you dig, the older the rock layers will be)
Fact: In the Olympic Mountains, older basalt, metamorphic and sedimentary rock is found under younger sedimentary rock.
Chromosome Theory (Chromosomes contain genes, which code for proteins, which give organisms their traits)
Law of Segregation (only one allele from each parent gets passed on) and Independent Assortment (most traits are not connected to each other)
Fact: Sexually reproduced offspring of plants we grow in the classroom show many traits that are similar to their parents.
(For teacher reference: see videos of lesson here (1st half) and here (2nd half).)
End of Unit "How Scientific Is it?" Instructions:
Watch this ~6 minute video on fact, law, hypothesis, and theory from PBS's "It's Okay to Be Smart."
In groups, complete letters G-L of the "How Scientific" activity with the following instructions projected on the board.
How Scientific Is It?
How do we decide that something is scientific versus something that is unscientific?
On your handout and just below, you will find six knowledge claim statements.
1) Read each of the knowledge claim statements with your group.
2) Discuss and agree on an order to the claims from that which you deem least to that which you deem most scientific.
3) Place the claims on the spectrum from less scientific to more scientific.
Less scientific <——————————————————> More scientific
4) Justification: Be ready to explain to others the justification you used for your placement of each item on the spectrum.
Knowledge Claim Statements (project all of this on the whiteboard)
G. I believe in evolution.
H. I’m convinced by the scientific evidence, such as FAME, that the theory of biological evolution explains how life changes on Earth.
I. Evolution is just a theory.
J. Adaptation by natural selection acting over generations is one important process by which species change over time. The other three mechanisms of evolution are mutation, migration and genetic drift.
K. A family member, who I trust, told me that people didn’t evolve from monkeys.
L. In undisturbed areas, older sedimentary rock layers are found below younger layers. Fossils change a bit in each rock layer and show a progression of species changing over time.
Less scientific <———————————————————> More scientific
Follow-Through Activities: The teacher again drops a pencil and asks students questions to see if they can distinguish fact, law, and theory.
Lesson Plan Summary: The lesson involves a demonstration, two journal prompts, and discussions about the nature of science, specifically fact, law, and theory. This is mostly a behaviorist lesson because precise definitions of these is very important, but some cognitivist techniques are also used in the demonstration and discussion sections.