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INTRODUCTION: During my four years of
working as the Montgomery College project manager for a National Science
Foundation faculty development grant in the sciences, I heard a great deal about
the latest research in cognitive neuroscience—i.e., what we know about how the
human brain learns. During my sabbatical in the spring term of 2006, I spent
many hours reading the literature in this area, and learning much more than can
be contained in this brief article. However, a few notions stood out in my
reading. One key discovery was that learning is actually a physiological
change in the brain in which the neurons grow additional “branches”
(dendrites) reaching out to other related neurons, and then strengthen their
ability to transmit information more efficiently by adding layers to the main
signal pathways. Another was the importance of active learning-- that “the
brain that does the work is the brain that learns.” (David Sousa, p.
123) A third was that our brains are naturally inclined to try to figure
things out; thus, novel events (which provide unexpected stimuli to the brain)
are an excellent means of providing motivation and enhancing learning. In the fall of 2006, I taught an expanded version of an elementary algebra class, designed for students who needed extra support in mathematics. In this developmental course, many students have “seen” most of the content before, but often aren’t able to recall or use the ideas. My goal was to design a learning activity for this class that would specifically put into practice some of the “brain based” strategies I had been learning. The structure of the lesson would provide an opportunity for students to connect with prior learning, try out new ideas in a safe environment, physically manipulate models representing abstract concepts, engage the content orally and in written form, have opportunity for practice, and finally reflect on the new learning. The specific concept of this lesson was
properties of exponents, but the various educational structures in the lesson
could be adapted to a variety of content areas. Some examples of adaptations in
chemistry, English, economics and other disciplines are described later in this
article. The entire activity was completed in one
50-minute class period. PURPOSE
SUPPLIES
DIRECTIONS: 1. Self-Assessment
and Class Results A. Display the list of six equations
(Supplies A below) on the
board or others means. Direct students to use their own paper to write the
numbers 1 through 6 and then identify each of the six equations as True or
False. They are NOT to copy the equations. B. After students have finished, distribute
the index cards with arrows on them. Tell students that an arrow pointed up
represents True, an arrow down represents False. Ask them to hold the index card
so that the instructor can see their selection for each statement. C. Move through the list item by item,
asking the students to show their selection for that item. Count the responses
for each question and tally them next to the statement on display. What is happening: Students are
activating prior knowledge (if any) in preparation for new learning activities.
Any previously “grown” neural networks are preparing to expand and
strengthen; even very weak past learning will be physiologically prepared to
make new connections. Having the students use the cards to respond allows the
instructor to see results without the interference of peer pressure to change
answers or the fear of giving incorrect answers in public, both of which happen
with a “raise your hand” type of response. Brain research reveals that
the anxiety about being “wrong” can chemically block the brain’s ability
to learn by preventing transmission between dendrites. 2. Mini-Lesson
on Brain Science Give the following brief background on dendrite networks. Showing a basic diagram of some neurons with dendrites is helpful and can be located via the resource list below and in the On Course text, page 179 (where you will find additional information about how the human brain learns). “When you learn, you are using thousands
of brain cells called neurons. Neurons are made up of a main cell body, a long branch
called the axon, and many branchlike extensions called dendrites. Neurons
communicate with each other across gaps called synapses by sending chemical
signals from the dendrite of one to the axon of another. The more you
learn, the more extensive your dendrite branches become and the thicker and more
efficient your axon gets at receiving and using the signals. All of you
have grown different kinds of neural networks for working with exponents: some
of you have only developed networks for working with number exponents but not
variable exponents; some of you developed your exponent networks several years
ago but because you haven’t used them they have shriveled; some of you
developed strong networks for exponents and practiced the ideas in a recent
course so the network is healthy and efficient. The goal for this class session
is to build or reinforce a strong exponent neural network so you can truly
understand how to work with exponents and, as a consequence, earn a high grade
in this class.” 3. Hands-On
Activity A. Have students select a partner (if
needed, one group may have three students). Ask one student in each pair
to come to the supplies location and pick up one set of cups and a worksheet for
each group member. B. Using a set of cups, tell the students that blue cups will represent variable “a” and red cups variable “b.” Ask, “What does an exponent describe?” Guide the replies if needed to the answer: “The number of times a base is used in multiplication.” C. Ask for a volunteer
to help you to demonstrate the activity. Represent a3 by
positioning three blue cups (upside down) next to each other on a desk; ask the
volunteer how to represent the expression (a3)2.
Help the student if needed to position three more blue cups in a group next to
the others, resulting in six cups. Ask, “How else could I describe what
I have here, using exponent notation?” Obtain the answer a6. D. Next, demonstrate modeling exponent
expressions in fraction form. To provide a visual “fraction,” put the
“numerator” cup(s) up on a stack of books, the chalk or marker tray on a
wall mounted board, or some other raised platform behind the area where you put
the “denominator” cup(s). As an example, represent the fraction b/b by
placing one red cup on the upper level, and another red cup on the lower level
directly in front of it. Ask, “What value does the expression b/b
have?” Obtain the answer “1.” E. Ask for another volunteer to model the
expression b6/b2. (They should have six red
cups on the upper level, and two on the lower level.) Illustrate that two
cups in the upper level can be matched with two cups in the lower level to make
“1” as before, with four cups remaining. Ask, “What expression
describes what we have left?” Obtain the answer b4.
F. Direct the pairs of students to use their
sets of cups to model the six problems on their “Properties of Exponents”
worksheet (Supplies B below) and complete the equations in the first column of
the table. What is happening: Students are
physically modeling the abstract concept of exponent; this gives an opportunity
for neurons in several different parts of the brain to participate in the
learning process. In addition, the unexpected use of the cups meets the
brain’s desire for novelty in the environment to encourage learning. In our
class, we had a lot of fun playing around with the modeling, and laughter is
well-documented to enhance oxygen levels in the brain as well as trigger the
release of endorphins which add to the brain’s ability to focus and pay
attention to a task. A. When finished, have one student in each
pair collect the cups and return them to the supplies area; then direct each
team to join another team to form a square [If there is a trio, they can stay a
trio; if there is an extra pair, identify one of the stronger students in the
class and ask that student and his/her partner to work by themselves for the
next activity.] B. Tell students to INDIVIDUALLY review the
statements they just wrote in column 1 of the “Properties of Exponents”
handout, and complete as many of the properties in the second column as they can
at this point. After a few minutes, direct students to share their
results with their group and work to complete the entire column. C. Next, display the correct answers to each
of the listed properties and address any questions the students may have about
the results. D. As a closing activity, display the
original True/False activity again (Supplies C below); direct students to individually identify
their answers on their own paper. Ask for a volunteer to provide their
entire list of answers; review for correctness with the class. Direct the
students to compare their present results with their (pretest) answers from the
beginning of class and welcome volunteers who are willing to share their
changes. E. Assign appropriate practice problems for
homework; if time remains, have students do selected problems for class work. What is happening: In these steps,
the student is attaching meaning to what has been discussed, reinforcing the
specific neural networks that were “grown” for that content. Students have
an opportunity to reflect individually on what is learned. Then, they have an
opportunity for discussion; the student speaking at any given time is adding to
his/her own learning network. Closure gives the student a final opportunity to
practice the content, increasing the likelihood of retention of the content. EXPERIENCES In the past, when teaching this topic, I
would typically just write all the properties of exponents on the board as I
talked about each one, do a handful of examples of integrating the properties,
and then assign some practice problems which many of the students would do
incorrectly despite my previous explanation. I have found myself bored by the
lesson on exponents, so I knew my students probably felt the same. This time, my
class was intrigued from the minute I walked in the room with the bags of cups
in my arms! The “novelty factor” is so important to creating
motivation and building memory
and retention, and it doesn’t take much to create it. During the cup activity, there was some
hesitation about exactly what to do, so I ended up doing some individual
demonstrations around the room to support the activity. One pair of young
men was especially reluctant to pick up the cups and move them around.
Once the pairs got going, however, there was enthusiasm and an occasional
argument about the right way to model a problem. After the students moved
into groups, I could tell from spot-checking the worksheets that the extensions
to the general properties were happening. Several students volunteered
their closing results on the True/False activity, with one student nearly
shouting, “I didn’t know half of them at first, but now I got them all
right!” OUTCOMES A couple of incidents helped me to see some
direct positive impact from the day’s activity. A couple of class
periods later, when we were using exponent properties in a new topic, I heard
one student say to another, “You know, like the red cup things we did.”
He was trying to show the other student why (x2)3 was the
same as x6, NOT x5. So he placed his two fists
together on the desk, first to the left, then in the center, then to the right,
to illustrate that there were three groups of two to consider. A more general piece of feedback on thinking
about their brains came in a response to a journal prompt, “What one thing is
your instructor doing that is helping you to become successful in this
course?” Two different returning adult women indicated that they
appreciated hearing about how their brains learned. They both said it made them
feel better to realize that one reason they didn’t learn new things as quickly
as some of their class members was that their neural networks had “died
back” from lack of use, but that they could “regrow” those networks just
as effectively with practice. On a more concrete note, I decided to make a
comparison of final exam performance on this topic between this class and my
classes which included this topic in the previous semester. I found that of the
twelve points assigned to assessment of exponents, in my previous semester the
average earned score was 6.6 of 12. For this current semester, the
average score jumped to 8.9 of 12. This improvement was impressive enough
that I will definitely use the activities in that topic, and other topics as
well, in my future algebra courses. ADAPTATIONS FOR OTHER DISCIPLINES: The general flow of the lesson is one that
can be applied in any content area with some adaptations. 1. Self-Assessment
and Class Results: If you are teaching a subject which is not a
review for your students, do the self assessment on previous content which is
relevant to the new lesson. For example, in a chemistry class with a
lesson on balancing equations, the self-assessment could be about writing the
correct chemical notation for specific compounds. [Eg, sodium chloride =
NaCl.] 2. Mini-Lesson on
Brain Science: Students in any subject area seem to love
hearing about the way their brains learn. Rita Smilkstein (see Bibliography) is
an English teacher who asks her students to draw their neural networks before
and after they learn a new concept, to emphasize their control over the learning
process. After you’ve talked about these ideas with your class (or had
them read about the basics) you will find it easy to refer back to this notion
on a daily or weekly basis. 3. Hands-On
Activity: Instead of having students use plastic cups and talk
about exponents, perhaps you’ll have students do a scientific experiment,
role-play a piece of literature, or create a 3-D model of the Battle of
Gettysburg. Bring in a costume, move the chairs around, play a piece of
music—the possibilities are endless! 4. Reflection and
Extension: Give students a chance to process individually, in
pairs or small groups, and then finally extend their understanding. For example,
in an economics class, after learning about the ways that the Federal Reserve
can affect inflation and output in the US Economy, students could individually
draw graphs representing these two effects, then compare graphs with another
student. Finally, students could be asked to identify a specific instance
in US
history which illustrates these effects. Each of these stages helps the neural
networks to grow and enhances retention. SUMMARY While doing my research and reading, I
became convinced that as educators we cannot ignore the findings of cognitive
neuroscience and then wonder why our students are unsuccessful. As I work
to apply the principles that I have learned (and will continue to learn), I can
see that knowing what is actually occurring in my students’ brains helps me to
design classroom activities that better fit their natural abilities to learn.
BIBLIOGRAPHY The following is a partial list of resources
I have found helpful in my quest to learn more about learning and the brain. Bransford, John, Ann Brown and Rodney
Cocking, eds. How People Learn: Brain, Mind, Experience, and School
(Expanded Version). Brier, Downing, Skip. “Becoming an Active
Learner.” On Course: Strategies for Success in College and in Life (5th
ed.), Houghton Mifflin, 2008 Jensen, Eric. Brain Based Learning
(Revised Edition), San Diego: The Brain Store, Inc., 2000. ---. Teaching with the Brain in
Mind (2nd Ed), Alexandria, VA: Association for Supervision and Curriculum Development, 2005. National Research Council. How
Students Learn: History, Mathematics, and Science in The Classroom, Smilkstein, Rita. We’re Born to
Learn: Using the Brain’s Natural Learning Process to Create Today’s
Curriculum, Thousand Oaks, CA: Corwin Press, Inc., 2001. Sousa, David A. How the Brain
Learns (3rd Ed), Thousand Oaks, CA: Corwin Press, Inc., 2006. Zull, James. The Art of Changing
the Brain, More sources on the Web: http://Help4teachers.com
Dr. Kathie Nunley’s Layered Curriculum Web Site for Educators (designed more
for K-12, but many interesting articles) www.funderstanding.com/brain_based_learning.cfm SUPPLIES 1. -42 = -16 3. (bc)4 = b4c4 4. b5/b8 = b3 5. (c7)4 = c11 6. (3b/2c)2 = 3b2/2c2
B. Properties of
Exponents: Modeling Activity (used in Step 3) Use a blue cup to represent “a”; a red
cup to represent “b”. Stack two textbooks on your desk to create a
“numerator” for fractional expressions. With your partner, use the cups to model each of the expressions in the first column, and then complete the equation. Do not go on to the second column at this time.
C. What Did We Learn?
(used in Step 4) 1. -42 = -16 3. (bc)4 = b4c4 4. b5/b8 = b3 5. (c7)4 = c11 6. (3b/2c)2 = 3b2/2c2 --Deb Poese, Faculty, Mathematics and
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