Labs for the beginning of the school year
Let’s start things off on the right science foot by incorporating some hands-on science activities in the first two weeks of school. I have chosen a couple of my favorite labs that will actually work in both Elementary and Secondary class rooms. They are both simple and use common, easily acquired materials.
- Rainbow flowers
Who doesn’t enjoy getting a bouquet of flowers? If you can learn some cool Botany facts along the way, then it’s even more fun. Coloring white carnations may seem a bit old fashioned, but there are some very interesting things you can learn from this experiment. Although I teach High School science, this particular lab works well with all grade levels.
All you need are white carnations, several glass jars or beakers, water, food coloring and scissors. Tip: leave the flowers out of water for about 24 hours before you do this experiment. You want them a bit “thirsty”.
On the day of lab, cut about an inch or two off of the flower stems and cut them at a bit of an angle. Then place water in the glass jar and add 2-5 drops of food coloring in the water. Stir the mixture and then add the flower. You should see a color change overnight, but leave them in longer to see if the color deepens. Added bonus: If you do not want to stir the mixture, place the drops in at the beginning of class and within 30 minutes, the food coloring will have diffused evenly throughout the water. This is a tangible way to illustrate that particles are in motion. Even though we cannot see the atoms moving, we see evidence that they are colliding into one another and moving the food coloring around. It also demonstrates equilibrium. So much learning from such a simple lab!
For elementary ages, you have a visible method of showing your students that water flows from the bottom to the top of a plant. You can ask your students to come up with all kinds of hypotheses, including which color they think will color best. You can try mixing colors (red and blue to make purple) and then ask if they think the flower will turn purple or if they think they will see some red and some blue separately on the flower.
For older grades, this lab works well when teaching about xylem and phloem that conduct water through plants. Also, you can place a plastic bag over the flower and a few leaves at the beginning of class. By the end of class, you will have demonstrated transpiration.
Make certain that you get enough flowers that you can use a variety of colors. I like to check with local florists about two weeks ahead of time. I ask them to set aside any flowers that are getting too old to put into arrangements or any ones that get damaged. Most are happy to save a few for me over a two week span and then I do not have to spend any budget money on flowers for this lab.
Another great benefit of this lab is that your room smells great for a week or more and it’s a very colorful beginning to your school year! I teach Biology and Chemistry, so this is one of the few times that my room actually has a pleasant odor!
Growing Gummies
A science lab using gummy bears? Count me in!
In order to demonstrate osmosis (the diffusion of water through a semi-permeable membrane), there is no better semi-permeable membrane than the gummy bear.
To perform this lab, you need a bag of gummy bears, glass jars or beakers and water. You simply place one gummy bear in a glass of water. Make sure that your little bear has a lot of water, and room to grow. You need about 3-4 inches of water over his adorable gummy head. Let this sit overnight and in the morning your gummy bear will be much larger and have the consistency of gelatin. The water has diffused right into him.
When you get the bear out of the glass, use a large spoon and be very careful. You will be able to see all the features, such as his nose and toes, just on a larger scale.
Students always ask if this is edible. The answer is yes. But I never let my students eat it because we use chemistry beakers and I cannot ensure their cleanliness. If you used a clean drinking glass or a clean glass jar, then you may let the students devour the bear. If you do this, make certain that you make enough for your whole class.
This is another lab that can be used by Elementary as well as Middle and High School classes. I use this lab when I teach about colloidal suspensions or osmosis.
So, I hope you have enjoyed these first two experiments. I am trying to make the start of your year both colorful and sweet!