Thursday, September 19, 2013

Watch a Plant Drink!

This week we finished up our unit on the needs of living things. We have learned that all living things breathe, grow, and, and change. We have also learned that all living things need food, water, and air to survive. We learned about several differences in living things as well. For instance, we learned that fresh water fish drink water through their gills and salt water fish drink water through their mouths. We also learned that plants make their own food. 

We learned that the plant's roots carry water up its stem and that its leaves carry sunlight down the stem and that the plant uses these things to make food. 

To illustrate how the stem works kind of like a straw, we did a little science "experiment". I posed this question to the students:

"What do you think will happen if we put this celery in purple water and leave it overnight?" 



I gave each student a post-it note and had them write down their predictions. They had some really great ideas!









Today, we looked at the celery again to see what had actually happened. If you look closely you can see that the veins in the leaves turned purple as well as some purple creeping up the stem. 


We took some time to talk about our predictions. I asked the students why they made the predictions that they made. Several students thought that the celery would grow because they know that plants grow if you water them. Others thought that the celery would drink all of the water because they had seen plants that had been watered and then seen that they were dry again in a few days. They thought that the plant would drink up all of the water because we had learned that plants drink water. All of these predictions show great thinking skills! The students looked at things that they knew from their personal experiences and used them to predict what might happen in a new and different situation. We talked about each situation and learned why these things didn't happen. I explained to the students that a plant cannot grow without roots and soil and that the celery could have used up all of the water if we had left it for a much longer time or used much less water. 

Several students also predicted that the celery would turn purple because of the purple water. I asked them to explain why it turned purple and they explained that the plant sucks up the water from the roots to make food and that the stem brings water up. 
I had these students put a check mark on their predictions because they had predicted what had actually happened. I had the other students put an x, but we discussed how any prediction that you can explain or support is correct. We only put an x to show that it wasn't what really happened-not to show it was wrong. 





















This was a fun way for the children to learn about making predictions.  They were all very excited to do an experiment and couldn't wait to see if what they had predicted had happened. It was also a good opportunity for them to learn that wrong answers aren't always wrong. Oftentimes they can help us learn!

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