Elise Nguyen
Outreach Summary
Partners: Emily Crespin
Courtney Dowd

Photosynthesis with 3rd Graders at Fort River (approx 16 students ages 9-10)

The three of us did a photosynthesis experiment with the third graders to illustrate that we see photosynthesis in everyday life, and that through photosynthesis will plants continue to be in existence. The concept is the synthesis of chemical compounds with the aid of radiant energy, most importantly sunlight, changing the formation of carbohydrates from carbon dioxide and a source of hydrogen (commonly water) in the chlorophyll-containing tissues of plants exposed to light.

Since our objective audience is third graders, it is extremely important to explain the process in an simple but thorough manner for them to capture the idea. We did not use much resources and references as far as the Internet and books, but approach our teaching experience more with hand-out experiment. We feel that the students can understand the idea more if they themselves can see the changes in the elodea over the weekend, or put together the molecules of sugar, water, oxygen, or carbon dioxide. Moreover, it is so much fun to build models and do experiments than to listen to someone lecturing about photosynthesis. We have two different parts of our lesson. First, we do an experiment with the elodea and watch the bubbles change over a twenty minutes span of time. Second, during that twenty minute period, we let the students build their own models of carbon dioxide, water, sugar, and oxygen with gumdrops and toothpick.

We put a strand of elodea into a small test tube and fill it with water, then flip the test tube and submerge it in water. It is essential during this stage to completely push all the air in the test tube out to be able to observe the bubles in the test tubes. The students must mark the intial point of where the water is, and let the test tube in the water bath for a period of twenty mintues. Afterward, they should observe that the level of water has significantly decrease since photosynthesis has taken place. The objective is to demonstrate that light is needed for the plants to go through any transformation. Therefore, we test different environments for the plants with the five different groups. One was right next to the window, where the sunlight is perhaps most penetrated. Another was covered in a blanket of darkness, hence no light can be expose to the plant. We also allow one experiment to just lie under the light energy of the classroom.

We also let the students build various models of the components essential for the process of photosynthesis. Gumdrops and toothpicks were distributed among the groups, and each student has an opportunity to pick which molecult he/she would like to make. Obviously, the sugar molecule is popular since it is the largest and most complicated. We group several students together to collaborately work together and form the molecule. They are very excited because they could play with candy and learn about the molecules at the same time. After everyone is done with his/her molecule, each student was to stand up and share with the class his/her molecule. The most thrilling part for the students of course is being able to eat their molecules. Some even decide to create their own molecule, simply from putting together different elements and forming a unique shape through various gumdrops.

We did not conclude the result of the photosynthesssi experiment due to the lack of time. Nonetheless, the teacher promised that they would observe and finish the lab on the following Monday. Overall, the whole experience of teaching went smoothly. It was a little chaotic with all the kids running around, but they are so energetic and eager to learn, it was all worth every effort. It was exciting for me just for the fact that I am back in an elementary school with all the memories of a long time ago (maybe not as long as it seems like.) What could be done to make it more sucessful, I think only in the organization department. We were not used to how to group the students, pair them up into groups, give them proper directions. I think that’s the important step in teaching anything, particularly science, to give clear instructions. Overall, it was very exciting.


OUTREACH EXPERIENCE:
Courtney, Elise and I Teaching 19 3rd graders (ages 8-9) at Elementary School

We taught the kids the basic mechanics of photosynthesis through the use of gumdrop molecules and an elodea plant experiment. We received a copy of a worksheet that the children had about photosynthesis, as well as the teacher’s experimental procedures that go with it. Because the experiment was predetermined, we did not need to spend any time working out experimental procedures. The experiment involved taking a 8 centimeter cut of an elodea plant and putting it in a test tude filled with water. The test tube was then placed upside-down in a tub half filled with water. The tubs were then placed under a light source and left for twenty minutes. The idea then was that the plants would produce oxygen and an air bubble would collect in the test tube. It would be possible to then measure the amount of oxygen and draw conclusions as to the reate of photosynthesis that occurred. In planning the experiment, we realized that it would be best to have something photosynthesis-related for the children to do while they were waiting to see the results of the elodea experiment. We decided to allow the children to build molecular gumdrop models of the molecules involved in photosynthesis. After the children performed this task, we would all be able to go back to the elodea and measure the amount of oxygen produced.

Although I thought we were fairly well prepared, there ended up being a few things that went wrong in our experiments. First of all, the elodea experiment did not yield observable results after twenty minutes. This problem was remedied by making a decision to leave the plants over the weekend and then measuring the amount of oxygen produced. While this is a fine solution, we will not be able to be there to participate in and discuss this part of the experiment. The other problem we encountered was that of organization. I always thought that teachers should be very organized, but after our experience today, I understand why they sometimes are not. We planned fairly well for the molecules but we did not have a set enough procedure and I think that really hurt us. Because we had not planned on an activity that would take each group the same amount of time, the groups finished at different times and ended up goofing off more than discussing the molecules. This would have been avoided had we more accurately judged the amount of time it would take the children to build the various molecules. However, I think that given the amount of planning we did, the experience went very well.

This experience encouraged my thoughts about teaching science. Teaching children has always been an enjoyable experience for me and Outreach showed me that teaching science is a great way to satisfy the children's curiosity. This makes it a very rewarding experience.

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