Petri Dish Science and Art Craft: Original Lesson Plan

Petri Dish Science and Art Craft

Original lesson  for informal educational environments by Rachel P. Riendeau

First used at Knight Memorial Library's Science Craft Mania, July 21, 2014

Providence, RI

25 minute sessions

GATHER: Supplies for each student.

1/2 plastic Petri dish (via online suppliers) OR bottom of clear round plastic bottle/lid

1 circle, traced in petri dish, of 2-4mm thick craft foam sheet

1-3 toothpicks

1 washable cup

1 permanent marker

washable markers

PVA (Elmer's) glue

glitter OR glitter glue

color print outs of interesting bacterial growths on Petri dishes

sample of finished craft

optional: small items (flat back rhinestones, shapes punched from leftover foam, etc.), scissors (older students), long Q-tip/cotton swab (for demonstration)

SHARE: Briefly present to your students (about 5 minutes).

            Can you see all the germs on my arm?

            Neither can I. There's lots of good and bad germs on our skin, in our bodies, and in the world but they're too small to see with your eyes.  You need a microscope,. or you can see them when there are hundreds and hundreds living together in groups called COLONIES.

            Have you ever been to the doctors when your throat hurts and they take a long Q-tip like this (demonstrate) and swab the back of your throat? That's because they're taking some germs from your throat to see if any are STREP (Streptococcus pyogenes) germs.

            Scientists feed the germs, pouring different types of food, called AGAR or GROWTH MEDIA, into small clear plates called PETRI DISHES. Then they transfer the germs from the Q-tip to the food on the plate by STREAKING THE PLATE, like this. If the germs like to eat that kind of food in the Petri dish, they will grow into COLONIES, which look like dots, all colors and sizes.

            Today we're going to imagine what COLONIES of different germs look like. First put the AGAR, here, into the PETRI DISH. Then use your imagination and markers to draw colonies on the AGAR. Often, more than one kind of germ grows on a Petri dish by accident. This is called CONTAMINATION.  To make your Petri dish more interesting, contaminate it: make more than one kind of pattern. Finally, put glue and glitter on the toothpick to STREAK THE PLATE. You can also make glue dots or glue on different things like dots and gems to make more COLONIES.

            Be careful to only use a little glue when you streak the plate so it will dry. I will come around to label your Petri dish with your name and the name of your germ--remember STREP, for example-- when you're finished, so start thinking of a good name. Any questions? Okay, ready to grow some beautiful germs?

                                                                   

LEARN: Vocabulary list for fun, for the board or  a hand-out.

microbe         bacteria          Strep               microscope                colony                        Petri dish

agar                growth media           streak the plate        contamination         culture

microbiology

REPEAT: Guide with structured directions as needed (15-20 minutes).

1. Put your circle of agar, the foam, into your Petri dish. Glue it down if it isn't snug.

2. Draw patterns of dots, lines, squiggles, and other shapes with the markers on your agar. 

Remember, you can have more than one kind of bacteria on a contaminated plate, so be creative.

3. Squeeze some glitter glue into the washable cup. Take a toothpick, dip it in the glue, and carefully dot or drag it across your Petri dish to streak the plate. Make more patterns.

4. You can also use the toothpick to dab dots on glue on small, flat backed items  to stick  bigger colonies onto your Petri dish.

5. Let me know when you are done. I'll write the name of your germ(s) on the back of your Petri dish, as well as your initials and the date, with the permanent marker. This label reminds you  what and when the germs "grew," an important detail for real scientists.

6. Clean up.

 SHOW: Real life examples. Google Images has great ones, or send me a message for those I've found.                                  

EXAMPLES: Note that students left these behind because they did not like them, so these are not the most impressive examples from Craft Mania.

   

                                                 

SOURCES:  Websites featuring examples of different Petri dish art

http://thedailydish2013.blogspot.com/

http://roganbrown.com/section/327584.html

https://www.etsy.com/shop/artologica?section_id=12459411

http://flavorwire.com/214209/microbial-artists-use-bacteria-to-create

http://www.smithsonianmag.com/science-nature/colonies-of-growing-bacteria-make-psychedelic-art-22351157/?no-ist=

http://magical-contamination.tumblr.com/

https://www.etsy.com/shop/ELINart

http://anatomy-uk.com/2012/10/15/laura-katherine-mcmillan/

Architectural Salvage Easel

The Neoclassical half-column of a base for something- heavy potted plant, patio table, bird bath-- was abandoned curbside the next street over. I raced back to my house, jumped into the car, and wrestled the heavy wooden piece of architectural salvage into the trunk without a thought what to do with it. The feet are shaved off unevenly and the wood was a dirty sorry shade of gray so I scrubbed, sanded, and painted it with leftover red from my sister's bedroom. By the time a coat of clear weather-proofing Rustoleum, I had thought how to put its tilted design to good use.

An easel of course requires a broad surface so I practiced my novice carpenter skills with spare metal joiner plates, scrap wood, and screws. There are a few nails I couldn't drive in fully that I left for hooks, and to mark it one of my inaugural clumsy carpentry projects along with the extra holes drilled in slightly wrong places. Despite these mistakes, the easel top sits sturdily on the base.

 The ledge was another feat of salvage. I unscrewed the loose curving legs from a dilapidated wooden chair, another curbside trash day treasure, and affixed them to the broad wooden surface with metal plates and screws. The holes where the legs were attached to the rest of the chair with wooden pegs function as pencil or paintbrush holders. I think the shape of the legs complements the Neoclassical base well, if I do say so. Now I need only a stool, or to use a collapsible folding chair, to paint en plen air. 

Americana Burlap Fence Hangings

I cannot encourage people enough to check local farms and farm stands for raw materials like burlap first rather than trotting out to a craft store and paying four times the amount for a newly manufactured, characterless roll. I saved the designs on the burlap bags I purchased for a few bucks from a local farm since the bold graphics summoned images of undulating corn fields and other midwestern Americana. I stitched the burlap into old wire hangers which looped over fence pickets. The hangings brighten the gray fence for the summer.

This potato sack, depicting a tiny mustached man with a boater raised to greet others as he cruises by on a penny farthing. I find the name of the chemical "to prevent sprouting" that may have been used dissonant alongside this genteel illustration.