Biology Class

So, which works better – soap and water or hand sanitizer? In the middle of a cold outbreak at the school, this has been a hot topic in the last few days. The Biology class decided to put the two to the test. With the invaluable help of Lab Assistant Mr. Louis Suttmann (right photo), the students started an experiment on Friday, September 29 to determine what is more efficient at getting hands clean. The first step was to prepare sterile petri dishes with three sections – one section for unwashed hands, one section for soap and water cleaned hands and the final section for sanitized hands. The students touched the medium with unwashed hands then proceeded to Lab Assistant Suttmann for a thorough washing of the right hand and returned to the classroom to have their left hands sanitized. Then, they touched the appropriate thirds in their petri dishes with washed and sanitized hands. The dishes were then closed securely and moved to a warm place over the weekend.

Here (right photo) are the results after 5 days, on October 4, 2017. You can see lots and lots of growth of bacteria and fungi. All sections of each petri dish showed growth: the unwashed hand section, the soap and water washed section and the disinfected hand section. It’s a bit too soon to come to any conclusion about effectiveness of soap over disinfectant. It was interesting to note that different bacteria/fungi grew in different sections.

Here (right photo) are the result on the final day – October 6, 2017. Seven days of growth. By this time it was clear that the soap and water washed hand was generally ‘cleaner’ than the disinfected hand. We had a discussion about why that might be and, like good scientists anywhere, accounted for possible errors (hands not washed or disinfected well enough,touching something else before the petri dish) and discussed the effectiveness of sanitizers and that perhaps the one used was not as effective as others might be. Hmmmm. Sounds like another experiment in Biology!

Final conclusion: WASH YOUR HANDS!!

Returning Student Spotlight

Name: Cornelius P.
Grade: 11
Nationality: German

Excerpts from his “Introductory Student Letter” in Literature and Composition 11.

“I grew up in Munich, Germany until the age of 10, and then started to go from a normal school to a boarding school. I went to a boarding school mostly because I always had trouble with grades and the school system in Bavaria itself. I am not made for the school system in Germany, because I need someone who helps me with my classes since I always have a hard time studying and learning things on my own. I went to many schools in my life and AIS is the best one so far, because I am able to get help from the teachers and they really want to help me succeed in life. In my old schools, the teachers didn’t care about me or how the students is able to pass the class.”

“This school has many activities and I like some of them. It is my fourth year at AIS and I like the soccer team the most. And for classes I like languages such as my own language, which is German, and English.”

There are many aspects of english class that I like, such as reading. I like reading, due to the fact that I enjoy finding out something new, that I’ve never read or heard before. I am a explorer who is travelling with his mind to unfamiliar places to find a new hobby or maybe something that I want to do in my future life.”

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