Tuesday, May 28, 2019

Flower Power - STEAM Program

Flower STEM activities,

This program was inspired by the saying "April showers bring May flowers". I thought flowers would be a great theme for this time of year, as many are blooming, but it's not too late to plant new flowers, either.

For this program we dissected flowers and learned about all the different parts and what they do, extracted the pH-sensitive pigment from rose petals and tested it, then made seed bombs with native wildflowers. 

[Click on any image to see larger]

Budget: About $45, not counting stock supplies
Ages: 5-10
Number: 15 kids (accompanied by adults)
Time: 1 hr to 1-1/4 hr


Flower STEM program
(all materials not pictured)
  • 2 bunches of alstroemeria flowers (or any flower that clearly shows anatomical structure; lily or hibiscus also work well, 1 flower per participant plus few extra)
  • 1 dozen red roses (8 would have been enough)
  • white vinegar
  • baking soda
  • plastic ziplock bags (snack or sandwich size)
  • water
  • seed bomb matrix (or about 2-3 cups each natural clay powder and compost)
  • 2 packets native wildflower seed mix
  • large mixing bowl or bucket
  • 45 small Dixie cups
  • 45 clear plastic shot glasses or test tubes
  • measuring spoon
  • mixing spoons
  • Exacto knife, scalpel, or razor blade (only to be used by instructor)

Activity 1 - Flower Dissection 

Flower Dissection Activity, STEM, STEAM
  1. I found a labeled diagram of the parts of a flower online, and handed out copies to each participant.
  2. I gave each participant a stem of alstroemeria flowers, though 1 bunch would have been enough since each stem has several blooms. (lilies work the best for visualizing all the parts clearly, but they can be pricey and some of them stink).
  3. We started with talking about the stem and leaves, discussing how the stem contains the xylem and phloem, which carries water and nutrients to the rest of the plant, and how the leaves use the energy of the sun to produce food through photosynthesis.
  4. Then we moved through the rest of the flower parts, taking them apart as necessary to better view the more internal parts. I cut them down the middle for them so they could see the inside of the ovary.
  5. I gave them a few minutes to study their diagrams and flowers as they wished while I prepped the next activity.

Activity 2 - Extracting Natural pH Indicator 

Natural pH indicator from flower

Flowers contain anthocyanins, which are water soluble pigments that produce shades of red, purple, and blue, and give many flowers their color. They are also found in red cabbage, berries, and other foods, and are responsible for some of the colors of autumn leaves. Anthocyanins are pH sensitive, which means their color can change under acidic or alkaline (basic) conditions.

In this activity, we extracted the red pigment from rose petals, and exposed it to an acidic solution and an alkaline solution and observed the color change.
  1. Each participant was given a small ziplock bag and half the petals from one rose (this was more than needed; each full-size rose is easily enough for 3 people).
  2. They were instructed to tear the petals into small pieces and put them into the bag. (It is easiest to open up the bag wide, and tear the petals over it, dropping the pieces directly into it.)
  3. Then they added a small amount of water (about 1 ounce, or 2 Tablespoons), which I had dispensed into Dixie cups, squeezed the air out, sealed the bag, and then smooshed the petals with their fingers for a few minutes, until the water becomes colored. (If it appears too concentrated, add a little water; if too dilute add more petals and smush longer.)

    Extracting anthocyanins from flower petals
  4. After the water became a definite purplish-pink color, indicating the pigment had been extracted, one corner of the bag was opened slightly, and the liquid carefully decanted off into 3 clear shot glasses/test tubes (It's okay if a few small pieces slip through).
  5. I then gave each participant a Dixie cup with a very small amount of vinegar (1 T) in it, and they were instructed (1) NOT to smell it directly, and (2) not to do anything until everyone was ready and I instructed them to. After everyone was ready, they were instructed to pour some of the vinegar in the first tube of rose extract, until they observed a change. They could add more after that if they wished. I explained that we would do nothing to the center tube of rose extract, because it was the control.
  6. Next, I gave them a small amount (1 T) of a baking soda solution (1 T baking soda in 3C water), and all added it to the third tube of rose petal extract, and observed the color change.
  7. I explained that vinegar was acetic acid, which we observed turned the pinkish-purple rose extract bright red, and the baking soda was an alkaline, or basic, solution, which we observed turned the rose extract a dark bluish-green.

    Natural pH indicator from rose petals

Activity 3 - Seed Bombs

I used a pre-mixed seed bomb matrix because (1) I only needed a small amount and it would likely have cost even more to buy the clay and compost separately, and resulted in excess leftover, and (2) it would save time and be less dusty and messy.
  1. I broke up the mix in a large bowl with a large mixing spoon. It is supposed to be ready to use, but seemed too dry, so I added a little water. (Of course I added too much, so I had to run get corn starch out of the supply closet to thicken it.)
  2. Then I added the two packets of seeds and mixed until it was well mixed and a good rolling consistency.
  3. I divided it evenly among the participants, and showed them how to roll it into balls, about 1/2" in diameter. After they rolled all theirs, they placed them in cups to take home.
  4. They were instructed to set them outside in the sun to dry well if they wanted to save them until fall to plant, or they could plant them now as is. The idea is to just toss them randomly in areas that are bare.
Making seed bombs

The package of matrix I got was enough for 15 participants to each make at least 6-12 seed bombs, depending on size. If we had not been pressed for time, I would have had the kids help more with mixing the matrix and adding and combining the seeds.

How It Went

I was very pleasantly surprised at how good of a turnout I got (15 kids and 9 adults) since it was the day after a holiday AND the last week of school. I figured everyone would have their days off or be distracted, and expected a low turnout.

Everyone seemed very engaged, if a little bit impatient at times. I was very impressed that one little girl knew what leaves did, including the word photosynthesis. Most of them did really well following directions, though every time they had to wait just a couple of minutes for everyone to catch up, or for me to hand out the next round of materials, they acted like it was taking forever, (have fun on those long road trips, parents), LOL! 

One girl got a little behind because she was so intent on tearing her rose petals into almost microscopically small pieces and had to be repeated urged to work a little faster and it was ok if the pieces were bigger. They were amazed when the water started turning purplish-pink as the pigment was extracted, and were very impressed with the color changes in response to added acidic and alkaline solutions. [Red cabbage is even more impressive as it has multiple pigments and covers the whole range of pH, but is very stinky to work with.]

I was impressed with how little mess they made making the seed bombs, and they really had fun doing it. I had to demonstrate to a few again how they were supposed to roll it into multiple small balls, rather than one large ball or mud pie. There was one girl who wanted nothing to do with it though, and said she was going to take it home and "make her mother do it". I was really impressed I made it through the whole program wearing white pants that were still white at the end!

One of my regulars cutely asked me, "Miss Jennifer, are you a scientist?" to which I replied, "I used to be, but now I'm a librarian, and that's even more fun!" [I have a BS in biology education, an MS in Microbiology, and in another lifetime worked in biomedical research.]

What I Would Do Differently 

Honestly, this one went really well as is, though it did run over just a tad. This was mostly due to several latecomers coming in a different times, causing me to have to pause and quickly grab them materials and catch them up. 

But it would also be great to just take the pigment extraction activity and expand it to a whole program by itself, by (1) providing them with additional (non-hazardous) solutions to test and determine if they are acidic or basic and (2) test the extract from a different flower of a deep blue or purple color. I had wanted to do a blue or purple flower as well, but the florist did not have any on hand, so if you want to do this, I would suggest ordering specific flowers in advance. This article has several suggestions for flowers, fruits, and vegetables that can be used; keep in mind some flowers, such as delphinium, are toxic, so be sure appropriate safety warnings and precautions are given.

One of the kids observed that the rose petals would leave pink-red marks when rubbed on the paper, so another activity that would go with this them could be using flower petals to "paint" with.

No comments:

Post a Comment