March 17, 2009 at 1:04 pm (MathEducation)
Tags: math, teaching
The other day a student asked me “why can’t I just punch the whole quadratic formula, with the numbers into it, into my calculator?”. Of course you can, but there’s some subtle ways that we write mathematical formulas that you have to be very detailed about when you put them in the calculator.
What I’ve seen students do is say out loud “negative b plus or minus the square root of b squared minus four a c all over two a”, and that’s the way they type it into the calculator. So if a is 1, b is -2, and c is 3, they proceed thusly;
-2 + √ -2^2 – 4*1*3 / 2*1 Enter
Then they do it again with a negative in place of the first positive, since they do understand the ± notation.
(Note that ideally they would use (-(-2) + √ ( (-2)^2 – 4*1*3 ) ) / (2*1) Enter.)
I’m trying to come up with a good learning opportunity to address this.
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March 16, 2009 at 10:38 pm (Hobbies)
I’ve just cast on a new knitting project; the first of the baby items from my Etsy store, picked by a friend for her new baby.
I don’t know where I read about .5″ of yarn for a long-tailed cast on, but it worked perfectly – I needed 175 stitches, so I measured roughly 90″, and I cast them all on the first time with only a shortish tail left.
I’m pretty sure I did my second swatch on 3.5mm needles, but I only have 3mm and 3.25mm in circulars. That’s what’s called for in the pattern, so I’ll start with them.
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March 16, 2009 at 5:03 pm (Uncategorized)
Tags: garden
A little check round on the web seems to say that everyone agrees the last frost date in Toronto is May 9. We’ve got 54 days still, then after the last frost there will be 84 days before we leave (hopefully!) on our summer trip.
While looking at the SFG site I noticed an Eco-Lawn product. I wonder if that would do well in our backyard, and between our square foot boxes?
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September 3, 2008 at 3:52 pm (Welcome)
I am an Intermediate/Senior (Grades 7 to 12) Mathematics Honours Specialist teacher in Toronto, also qualified to teach Computer Studies; I also have additional qualifications in Special Education and English as a Second Language. I am currently employed by the Bishop Strachan School in the Mathematics department, teaching grades 7 to 9. Some relevant sections from my resume are on the left-hand side of this page. Please feel free to browse around and leave me a comment – all comments are screened and are not made public unless you request it.
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April 30, 2008 at 3:48 pm (Uncategorized)
Their website at www.ncgs.org/stem has information relating to STEM initiatives specifically for girls and women. Includes things you would expect, like profiles of women scientists, and things you wouldn’t necessarily, like classroom climate tips.
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December 17, 2007 at 11:38 pm (Uncategorized)
I love the game called “SET” for patterning. My friend Sayaka at JUMP Math introduced it to me, and we spent a couple of happy lunch hours playing. The website for the game has a daily puzzle, plus several teacher resources including how to teach the mathematics behind the game.
Strangely, I have never played Blokus, although I suspect I soon will, since our grade 7’s are doing activities with pentominoes in the the new year! The website allows you to play online, either against the computer or against other players worldwide.
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December 13, 2007 at 11:07 pm (Uncategorized)
Is it too much to ask… to have a WordPress theme that is two-column, flexible width, and has a customized header image?
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December 2, 2007 at 6:00 pm (Uncategorized)
I laughed at first when someone told me that it’s always easy to find something to buy a teacher. Now I see that’s true… there are so many things I want to have in my personal toolkit!
Blank playing cards (http://www.dickblick.com/zz614/42/). So many uses! Write student names on them to shuffle and deal random groups, or pick student names at random. Create custom card games using vocabulary or math questions.
Noise level detection and control (www.gabstopper.net). I can reward the students when they keep the noise level at an appropriate level for a whole class. There is a physical version called the “yakker trakker”, but since I currently have a computer and projector available, the software version should be enough.
Jean Swanson’s book Poor-Bashing: The Politics of Exclusion;. http://www.btlbooks.com/New_Titles/poor_bashing.htm
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November 11, 2007 at 11:21 pm (MathEducation)
Tags: Grade8, PDM
I used this activity to review before a test at the end of our “Probability and Data Management” unit. It covers probability up to and including grade 9, in terms of expectations from the Ontario Ministry of Education. The questions are quite difficult – more difficult than the ones on the actual test! Students were allowed to use calculators during the bingo game. There are two sets of bingo cards in PDF, so each student’s card is unique.
Probability Bingo overview
Probability Bingo presentation
Bingo Cards (set 1)
Bingo Cards (set 2)
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November 11, 2007 at 10:12 pm (MathEducation)
Tags: Grade8, PDM
The NCTM publication “Navigating through Probability in Grades 9 to 12″ has an interesting data management activity called “One-Boy Family Planning”. Using the Chinese “one-child” family planning policy from 1979, students are asked to imagine that the policy says that families can have “one boy” rather than “one child”. A die is used to simulate the birth of a boy (odd numbers) or a girl (even numbers). Students run 20 simulations and track how many “children” are born before a boy occurs in each of the 20 simulated families.
I am using this activity as a make-up activity for students who didn’t do well in our initial data management and probability unit. Since the activity requires them to pool their data with other students, the attached document includes data for nine fictional students. The table can be selected, copied, and pasted into Excel. Students can also receive BTT10 marks for their use of Excel in creating the tally charts and graphs.
My data for you to use as you wish: oneboydata.doc
Link to the NCTM book to purchase: http://my.nctm.org/eBusiness/ProductCatalog/product.aspx?ID=12328
Shaughnessy, Michael. Navigating Through Probability in Grades 9-12. Reston, VA: National Council of Teachers of Mathematics, 2004.
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