Bacteria reproduce by binary fission. They break in half and one becomes two. I use this topic to link math and science when we study bacteria and viruses. I start off with the question: If you start with a penny and double it every day, how many dollars will one have in one month? Let the month have 31 days. At first, they think it might be a hundred dollars or a thousand. But I have them do the math by doubling the number 31 times and see what they come up with.
After a while,
Who are the top five most influential mathematicians? I have five in mind that are important and are helpful when teaching math as related to MathCounts. Many students do not know of any mathematicians and I think it is important to teach some of the more important and influential mathematicians. It is also possible to study some of the lesser known but just as important mathematicians, but that would be for a more advanced class. I usually have the students learn some basic facts and the date of birth using the Peg System. Here are my top five.
My first video dealt with dividing numbers ending with zero, such as 30, 40, 50 etc. See part A below. I will now show you how to divide numbers that do not end in zero. This is the math trick that we use in class to try and beat the calculator. It really gets kids interested in some math and it’s great to do when there is only a few minutes left in class. I believe in not wasting a minute of instructional time. My MathCounts team uses this mathematics trick to sharpen their wits and warm up before we tackle the harder problems in practice. I’m also happy to say that my MathCounts team took first place in our region and also finished in the top half at the state competition. Great job. I’m very proud of them for all their hard word.
Background Information
During the school year, I introduce an important scientist or mathematician almost every week. I believe it’s important to study the history of science and math as it puts the science content in perspective. I also try to give an equal amount of male and female scientists so all of my students may find a role model. Usually, I give the name of the scientist, a few items of what they did and the date and year of their birth. We memorize the year using the Peg system. I always give the birthday because it’s interesting to see the reaction of the students when they discover they share the same birthday as Einstein–pi day 3-14 , or Sylvia Earle, August 30th.
The Lesson Plan
Since we now have studied sixteen scientists, I came up with a new lesson plan that includes writing about the scientists and using the sweet sixteen NCAA college basketball format. First, we list all sixteen scientists on the Scientist16 sheet. The student then flips a coin to decide who moves to the next bracket. I’m sure you could find other ways to move the scientists to the next bracket. Students continue to do this until there is only one scientist left. The final scientist may or may not be the person that the student feels is truly the most outstanding, but their assignment is to write a report defending this scientist as the most influential in our society over the other fifteen scientists.
Discussion
This assignment may be a challenge as some of the scientists and mathematicians may not be as influential as Einstein, Curie or Edison. The goal is to get students to think about what is important and to develop their writing. The student should research the winning scientist to discover if any other important information is useful to help write the paper. For an 8th grade class, I specify that the paper should be a minimum of 250 words. For the 7th grade I specify one well developed paragraph of five to eight sentences. You can modify this based on the grade level and time needed to grade. Next time, I’ll give you the list of scientists and mathematicians that I use in my class. Are any of your favorites on the list? Till next time…
I use Club 91 as a fun way to sharpen my students’ math skills. If they can beat the calculator, then they can join Club 91. To divide by 91, one must keep in mind that their are two routines to know before you begin. Today, I will show you what to do when the number to be divided ends in zero. The next lesson I will show you what to do when the number does not end in zero. After you give this a try, practice in your mind so you can beat the calculator. Have fun.
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