for studying stimulus-response behavior (Appendix A; see Supplemental Material with the online version of this article). The students
were then asked to predict how planarians will react when placed
in solutions of caffeine and sucrose. They conducted experimental
trials using caffeine and sucrose following the procedure shown in
Appendix B (see Supplemental Material).
As pre-laboratory activities, before conducting the experiment they
designed, these students had already conducted investigations using
planarians, similar to those in SEADAP lessons 1, 2, and 3 (see
plans.pdf). These SEADAP-related lessons allowed them to hypothesize and implement experiments using other substances, such as
alcohol and nicotine, in addition to sucrose and caffeine.
After completing the pre-laboratory experiments, the students were
asked to design their own experiment. To facilitate higher-order
thinking, the teacher asked such questions as “What other solutions
could be tested?” and “In the real world, what other combinations
of substances would consumers use?”
The students considered observing the effects of caffeine in a popular soft drink on students, teachers, and staff. However, there were
ethical considerations when trying to work with human subjects.
They were able to videotape an interview of one staff member who
was addicted to a popular soft drink and was advised by her doctor
to reduce her intake.
The students wanted to gather more information related to a
combination of solutions of caffeine and sucrose. In response to the
questions above, a group of students created a new and different
experiment using caffeine, sucrose, and Monster Energy drink. The
students wanted the planarians to travel in one direction instead of
crossing and recrossing grid lines of graph paper (as described in
Appendix B; the authors provided input for the lessons in the SEADAP program, and the protocol in Appendix B was designed for
lesson 3 as presented at https://medicine.temple.edu/sites/medicine/
files/files/seadap_lesson_plans.pdf). Via trial and error, the students
decided to measure a 5 cm distance (d) on a groove of a print developing tray. The teacher prepared the 10 mM stock sucrose solution
and 10 mM caffeine solution; the Monster Energy drink started at
100% solution. The students made diluted concentrations (serial dilutions) of caffeine or sucrose from the 10 mM concentration stock solution prepared by the teacher.
The students designed and implemented the following protocol
(approximate periods of time required are shown in parentheses):
(1) Pour spring water into the groove of the print developing tray.
(2) Place a planarian in the groove.
(3) Record the time (t) it took for a planarian to travel 5 cm in
(4) Repeat the procedure for three trials using spring water with
three different worms. (20 minutes)
(5) Repeat the procedure above, using caffeine at concentrations
of 0.001 mM, 0.01 mM, 0.1 mM, 1 mM, and 10 mM for a
total of three trials, with a different worm and a different concen-
tration of caffeine for each trial. Change planarian between dif-
ferent concentrations so as not to affect the results. (25
(6) Repeat the procedure, using sucrose at the same concentrations of 0.01 mM, 0.1 mM, 1 mM, and 10 mM for a
total of three trials, with a different worm and a different concentration of sucrose for each trial. Change planarian
between different concentrations so as not to affect the
results. (25 minutes)
(7) Repeat the procedure, using Monster Energy drink at
0.01%, 1%, and 10% dilutions for a total of three trials, with
a different worm and a different dilution of Monster Energy
drink for each trial. Change planarian between different
dilutions so as not to affect the results. (25 minutes) (The
teacher showed the students how to calculate the dilutions
of Monster Energy drink. The velocity [v] was calculated [v
= d/t] for each of the three trials and the average velocity
During their experiment, the students observed some atypical behavior in the planarians. The behavior of some of the planarians was
inconsistent and the students questioned whether room temperature
affected the planarians or caused variation in the results, so they
adjusted the temperature in the room to make it the same for all
their experimental trials. Additionally, these middle schoolers learned
not to shake the table while doing the experiment, since this could
affect the results. They also thought the light in the room may have
affected the planarian, so they kept the light the same for all trials.
After taking the identified variables under consideration, the students
decided to conduct three trials; the data points in the graphs represent the average velocity of their trials (Figures 1 and 2).
At the highest concentration/percentage of sucrose, caffeine, and
Monster Energy drink, the planarians’ velocity decreased, and ste-reotypical movement increased. The highest average velocity
occurred at 1 mM concentrations of sucrose and caffeine. The planarians died at 1% and 10% Monster Energy drink dilutions. The
highest average velocity of planarians in the energy drink occurred
at 0.1% (Figures 1 and 2).
This student investigation addressed a real-world problem and
required higher-order thinking skills. The final products for assessment were a poster and an oral presentation. The teacher used a presentation rubric (Table 1) that includes the categories “Below
Standard,” “Approaching Standard,” and “At Standard.”
The students were also administered a test after SEADAP lessons
1, 2, and 3 were implemented and after the completion of the sucrose,
caffeine, and Monster Energy drink investigation (see Appendix E in
the Supplemental Material). The questions addressed student knowledge about the science of drug addiction, awareness about the care
and use of animals in basic science research, and awareness about biomedical research careers. On average the students answered nine of