When Science Experiments Work!

I am in my fourth year of teaching science and am enjoying every moment! My students continually challenge me to be a better science teacher and I am so grateful for these opportunities to grow as a teacher. 

We have been studying our second unit on the digestive system and I have created stations for the students to walk around, have short experiences and gather information on topics on digestion. I had a few stations set up in the classroom and then a few outside our classroom. We even have a model of the human body as you can see on the counter. Students enjoy pulling it apart and putting it back together again. 

I had students in groups of three or four. This station below had students put a cracker in their mouth and just let their saliva break it down for 30-40 seconds then write down the consistency of the cracker and what it tasted like. I received responses of "gross" and "smushy." And that the cracker was "tasteless" and "less salty." I let students eat a cracker normally after they consumed the mush. ;)

Another station had students counting their teeth and how many of the different kinds of teeth they have; incisors, canines, premolars and molars. They had a piece of apple they could eat while they answered questions about which teeth first bite into the apple and what is their shape and function. Then which teeth continue to chew the apple and how the tongue and lips help with eating the apple. I set out mirrors for students to use while counting their teeth and got some great pics! 

In our last lesson for this unit, there is an activity where we put starch solution into two test tubes. While we place amylase (an enzyme) into the one tube, only water goes into the other one. Then we test both tubes after 20 minutes for starch and sugar. When testing for starch, we use iodine and for sugar, we use Benedict's solution along with a warm water bath. I tried unsuccessfully to create starch solution in the past and this year, one of the high school science teachers created some and our experiment worked!!! I was so excited! The students were excited as well to see the colors of the iodine change in the presence of starch and the Benedict's solution change from blue to yellow as there was sugar after the enzymes broke down the starches. 

Above, you can see our iodine (starch) test. The slide on the left shows that there are starches and the one on the right shows no starches as they were broken down. 

The tube above is the Benedict's test showing the presence of sugar. This tube had the starch solution and the enzyme amylase which broke down the starches. The tube below only had the starch solution and water. It is so thrilling when experiments work out! 

Next up...the circulatory system! Stay tuned!