Idea Bank: Spooky Science (by Dr. Lara Pacifici)
All teachers face the challenge of teaching on holidays, such as Halloween. Student energy levels are
high, and it is often difficult to cover any actual course material while keeping students attentive and
engaged. The following activity presents an option for covering biology content while engaging
students in an investigation that highlights the spirit of Halloween.
Students enter the biology classroom on Halloween greeted not by their normal teacher, Ms. P, but by
Ms. Ivana Breakabeaker (their normal teacher dressed as a “mad scientist”). At their seats, students
find the following message:
Dear Students,
Ms. P. needs your help! She was last seen at school yesterday but is nowhere to be found today.
Authorities think that she was kidnapped (gasp!). The evidence left at the scene consists of one big
blob of … uh, we’re not sure what it is. Since it was here over night, authorities believe that it has
changed color. The four suspects that authorities think may have kidnapped Ms. P. are a witch, a
ghost, a werewolf, and a vampire. Authorities have specimens on file (they have been suspects
before!) in the following form from the suspects: wizard blood, ghost slime, werewolf slobber, and
vampire tears. Your job is to test each substance and determine whether it contains sugar, starch,
protein, or lipid. You will also test the substance left at the scene of the crime to compare to the
suspects’ samples. The suspects’ samples that contain macromolecules that match the “blob” must
have committed the crime. The authorities will use your results to identify and incarcerate the
perpetrator(s). Your substitute teacher, Ms. Ivana Breakabeaker, will help you today.
Students follow the procedure below to determine the composition of each sample. This is a basic
macromolecules test masquerading for Halloween. The wizard blood contains oil (lipid), the ghost
slime contains gelatin (protein), the werewolf slobber contains potato flakes (starch), and the vampire
tears contain sucrose (sugar). The blob is a combination of all four substances so should test positive
for all four tests.
__________________________________________________________________________________
PROCEDURE
A. Put on your goggles!
B. Perform each of the following tests on each of the 4 substances (a,b,c,d), as well as the blob (e).
Rinse your test tubes between each test. Use the same test tube for the same substance during each
trial. Record your findings in the table below. Each group should begin on a different test so that no
more than 2 groups are performing each test at any given time.
Test for Protein:
1. Put 2ml of each substance in a separate test tube
2. Add 3 drops of Biuret’s solution to each test tube and gently swirl. Proteins turn purple in the
presence of Biuret’s solution.
Test for Sugar:
1. Put 2ml of each substance in a separate test tube
2. Add 3 drops of Benedict’s solution to each test tube then bring it to the cauldron at the front of the
room. Let the test tubes sit in the cauldron for 2 minutes. Sugar will turn a different color from the
rest.
Test for Starch:
1. Put 2ml of each substance in a separate test tube
2. Add 3 drops of Lugol’s iodine solution to each test tube. Starch turns blackish blue in the presence
of iodine.
Test for Lipids:
1. Using the pipette, smear 1ml of each substance on the brown paper. Let the substances sit for 5
minutes. Lipids will turn brown paper translucent.
Results
Evidence:
Wizard
Blood (a)
Ghost
Slime (b)
Werewolf
Slobber (c)
Vampire
Tears (d)
The
Blob (e)
Macromolecules
Present:
Answer the following questions:
Which suspects were involved in the kidnapping? _______________________________
Why might these tests for macromolecules be useful in the “real world”? Recalling the function of
each of the macromolecules, brainstorm 2-3 instances in which these tests may be used.
__________________________________________________________________________________
Upon conclusion of lab activities, Ms. Breakabeaker finds the following note on her desk and reads it
to the class
Dear Ms. Breakabeaker,
Thank you so much for substitute teaching for me today while I go trick-or-treating with my friends,
the witch, the ghost, the werewolf, and the vampire. Sorry for the mess we left here last night – the
wizard slipped on the ghost’s slime and cut his elbow. The blood caused the werewolf to start
salivating and the vampire to start crying. Luckily I had a band-aid and everyone is fine. Please be
nice to my students because they are the best students ever. I have left a piece of Halloween candy for
each of them. Please tell them to have a Happy Halloween and I will see them tomorrow.
Sincerely,
Ms. P.
MATERIALS
Stock solutions:
(a) Wizard blood – 500 mL vegetable oil + 10 drops of red food coloring vigorously shaken
(b) Ghost slime – 2/3 box of plain gelatin + 500 mL water + 10 drops of green food coloring
(c) Werewolf slobber – ¼ cup of instant mashed potato flakes + 500 mL of water + 5 drops of green
food coloring + 5 drops of red food coloring
(d) Vampire tears – ¼ cup of table sugar + 500 mL of water
(e) Blob – 50 mL of vegetable oil + 1/3 box of plain gelatin + 1/8 cup of instant mashed potato flakes +
1/8 cup of table sugar + 300 mL water + 5 drops red food coloring + 5 drops green food coloring
At each table (stock solution makes enough for 5 groups):
1. Test tube rack with 5 test tubes labeled a, b, c, d, e.
2. 5 flasks:
a. 100 mL of (a) wizard blood
b. 100 mL of (b) ghost slime
c. 100 mL of (c) werewolf slobber
d. 100 mL of (d) vampire tears
e. 100 mL of (e) blob
3. Plastic pipette in each flask
4. Piece of paper bag
Set-up: 3 stations spread throughout room
Back station: Biuret’s solution in 2 dropper bottles
Side station: Lugol’s iodine in 2 dropper bottles
Front station: Heating plate with 500 mL beaker filled with hot water and Benedicts solution in 2
dropper bottles
Safety considerations:

Goggles should be worn by everyone in the classroom at all times during this activity

Students should be instructed on proper use of the hot plate and how to heat their test tube –
ideally there will be a submergible test tube rack the students can use tongs to set their test tube
in. Students should be reminded not to touch their test tubes when they come out of the hot
water bath and to wait until they are cool (put hand close to but not touching to detect heat)
before rinsing them out.

There will be a lot of movement around the room. Students should be reminded to watch where
they are going and to be very careful when carrying glass.

None of the chemicals should be removed from their stations – bring your test tube rack to the
station, use the chemical, then bring your test tube rack back to your table to analyze the
results.
When I did this activity with my 9th grade biology classes, they were engaged in the story line and had
fun trying to solve the mystery. There was a definite Halloween-ish atmosphere in the classroom
without forfeiting learning or progress in the coverage of biology content. This activity could be used
as a way to introduce macromolecules or to review them. It could also lead into discussions about
diabetes testing, kidney function testing, and cholesterol testing.
Overall, this activity is an effective way to acknowledge a day that is special in children and
adolescents’ lives while still doing our jobs as biology teachers. And what science teacher doesn’t like
getting dressed up like a mad scientist every now and then?