As the
United States of America moves even closer to fully implementing the Next
Generation Science Standards, it still amazes me that the majority of science
teachers who are implementing scientific investigations and experiments in
their classrooms are still heavily relying on labs that require students to
follow a series of steps, answer questions, follow more steps, and then answer
a series of even more questions. These laboratory investigations have
notoriously been deemed by science academic experts as cookbook investigations;
students are able to follow a series of steps, execute a series of actions, and
construct a product, usually a laboratory report, without contemplating the
importance of the steps conducted and the conclusions that can be drawn from
the data in the same manner that someone who does not know how to cook (like
myself) can physically bake an acceptable apple pie that can be later used for
consumption.
Cookbook
labs are typically easy to grade (answer keys and rubrics usually include
points being awarded for right and wrong answers) for the teachers, and they
are also easily completed by the students since these types of investigations
are typically up-front about the answers that students should expect at the end
of the investigation; students are essentially completing a laboratory
investigation that is supposed to confirm and already stated scientific fact.
Whenever students are expected to confirm an already existing idea, fact, or
concept, it does not take much creativity to literally change the collected
data from an experiment in an attempt to make it appear that the data collected
in the laboratory investigation actually does prove the concept under
consideration. These cookbook laboratory investigations are fantastic in that
the grader knows exactly what to expect, and the educator is able to identify
any issues that happened in the laboratory investigation in the event that the
data and analysis did not confirm the aforementioned concept.
Whenever I
was a student in middle school and high school, almost all of the laboratory
investigations that I completed were of this type. Whenever I entered the
classroom for my first year of teaching Physics, I was guilty of giving such laboratory
investigations to my students. Unfortunately, since my students were expected
to perform well on the Advanced Placement Physics Exam, it became apparent,
based on the questions on the official exam and my students’ scores on the
laboratory based questions, that the strategies that I used in the classroom
were not conducive to the type of deeper learning that the students were
supposed engage with. A change was needed.
After
attending an Advanced Placement Physics week-long training on Oak Ridge
Tennessee prior to the second year of teaching high school Physics, I came away
with a new form of a laboratory investigation – The Inquiry Based Lab, or, as I
like to refer to them, the “MacGyver Lab”. These laboratory investigations are
not fully-fledged open-inquiry labs, but are just open enough to allow students
to explore specific knowledge and skills that are required to be learned as a
result of taking my class.
An inquiry
based lab is actually quite simple to write and implement in your own
classroom. It consists of the following parts.
·
Prompt: The prompt is a single paragraph that
explains the context of the laboratory activity and what students need to do,
in general, to complete the laboratory activity. In theory, this is the ONLY
piece of information students need in order begin working on the lab. The remaining
parts are essentially how the laboratory investigation will be scored.
o Example: You and your partner will be
given one meter stick, one roll of tape, one stop watch, one constant velocity
battery powered car (that only travels in a straight line), ten tooth picks,
five paper clips, 100.0 centimeters of string, and mobile device such as
Smart-Phone or Tablet Device. You and your partner will use the materials given
to: Determine the average linear speed of the constant velocity car, the
average centripetal speed of the constant velocity car whenever the car travels
in a straight line, the period in which the constant velocity car travels in a
circle, the frequency in which the constant velocity car travels in a circle, and
the centripetal acceleration of the constant velocity car as it travels in a
circle.
·
Materials List: Students will have to create a list
of all materials that they used in order to accomplish all of the tasks
mentioned in the prompt. The students may only choose from the materials
mentioned in the prompt paragraph, but they do not necessarily have to use all
of the materials mentioned. This is why I like to refer to these labs as “MacGyver
Labs”; students have to use the materials in their raw form to create the
situations described in the prompt. And yes, I definitely list materials that
students do not need in order to complete the experiment.
o Graded on a scale of: Incomplete OR
Complete (2 Points)
·
Procedures: Students then have to setup the
experiments on their own using the materials that they have mentioned in their
materials list. If an item is mentioned in the materials list, students have to
explicitly state how the materials are used, and describe what the materials
measure about the experiment under consideration if they can be used to collect
data. Whenever students are writing their procedures, they must write the
procedures out in a series of steps that can be followed by anyone not familiar
with Physics; the students are generating their own steps to complete the
problem. This forces the students to understand the steps used in the
completion of the laboratory investigation. The procedure must be written in
such a way that at least three trials of data are collected for each quantity that
is measured.
o Graded on a scale of: Poor, OK, Good,
and Great (4 Points)
·
List of Measured Quantities: If a student collects ANY data from
the experiment, the student group needs to create a list of all of the
quantities that were measured in the investigation along with the measuring
device that was used to measure the quantity. This helps students stay
organized on what they are measuring, why they are measuring it, and how it can
later be used in calculations.
o Graded on a scale of: Poor, OK, Great
(3 Points)
·
Organized Data Table(s) of Measured
Quantities: As
student groups conduct their experiments, the students must organize their
collected data into a series of neat, organized data tables (or one data table)
that contains information that will later be used for specific calculations.
The data tables are to be completed with a computer program or with a
straight-edge so that professionalism is maintained.
o Graded on a scale of: Poor, OK, Great
(3 Points)
·
Variable List: If students use specific equations in
order to complete necessary calculations, the students are required to provide
a key that tells the reader what each variable stands for in a given equation.
If the same variable is used twice but the variable has two different
subscripts, then the student has to tell me what BOTH variables represent.
o Graded on a scale of: Incomplete OR
Complete (2 Points)
·
Calculations: Using their data tables, students are
to complete a series of calculations necessary to answer the information
contained within the prompt. Each time “determine” is used in the prompt,
students know that that is a specific calculation that is requested to be
performed. Therefore, one laboratory investigation may contain a series of
calculations. Students must write down the original equation (in variable form)
used for a calculation, must show substitution of experimental numbers, and
then must determine a final answer with acceptable units.
o Graded on a scale of: Poor, OK, Great
(3 Points) – Per Calculation Required
·
Written Summary of Calculations with
Conclusions: The
student groups then use their final calculations with units to create a written
summary of all of the calculations that were conducted along with the physical
significance of the calculations themselves. This is considered the traditional
“drawing conclusions” portion of a cookbook investigation.
o Graded on a scale of: Poor, OK, Great
(3 Points)
·
Laboratory Improvements: Students will then construct two more
paragraphs to explain how the laboratory experiment could have been
realistically improved if the students had access to other materials or
technology to help collect the data. The students are expected to critique the
preciseness and accuracy of the measuring devices used in their experiment, and
then compare these characteristics with the precision and accuracy of better
measuring tools that would yield more consistent results. Students may also
comment on how a change of their originally written procedures could have
somehow improved the data collection process of the experiment. This component
of the laboratory investigation allows for student self-assessment of their own
experimental designs and solutions, which connects back to the Science and
Engineering Practices of the Next Generation Science Standards.
o Graded on a scale of: Poor OR Great (2
Points)
At the end
of the investigation, students will have created a full laboratory report with
materials lists, procedures, data tables, calculations, and explanations and
justifications of their own calculations, and a full discussion of ways in
which the experiment could have been improved if given a different set of
materials and/or procedures. In this way, students create their own laboratory
investigations, they assess their own investigations, and they complete them in
a manner that is specifically unique (but structured) to their needs and
desires.
After
using these types of laboratory investigations in my own classroom, I found
that students performed better on in class assessments, and students performed
MUCH better on the official Advanced Placement Physics exams. While this
assessment seems to be a bit too advanced for your own students, keep in mind
that it can be adapted to meet the needs of your own students regarding the
grade level. I used these same types of laboratory investigations for my
general Physics classes and my Freshman Physics classes. By reducing the
complexity of the investigations themselves, you can adapt this type of
investigation to any grade level in which students can write complete
sentences.
In terms
of grading, the process is quick. With the grading scale specific to each
component (with at most only four possible points per component), I can quickly
and confidently award a score that is definitely an “OK” or a “Great”. If
students worked in groups of two (one laboratory group per class), I could
grade an entire class of laboratory reports in less than one and a half hours
(assuming a class of 35 students) (writing feedback takes longer if you like to
leave a considerable amount of feedback for the students).
As we move
away from cookbook laboratory investigations, and as we move closer to deeper
learning for our students, I encourage you to implement your own MacGyver labs.
If you do not believe that you can write a lab on your own, consider reviewing a
cookbook lab that you already give. Take the materials listed for the lab, add
a few materials as red herrings, describe the experiment in the prompt, and
then see if you students can use the materials to mimic the steps in the cook
book lab. In most of the Inquiry based labs that I gave in my own classes, I
drew inspiration from classic cookbook labs. Only slight modification was needed
to convert the cookbook labs into the Inquiry based investigations.
The post
was long, but I definitely wanted to provide a specific example of the type of
assessment that we need to start giving our students in place of assessments in
which students can reach a correct answer without knowing why.
And with
that, I am caching out!
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