Zero > 1, 2, 3...?

Today, Ms. Casper shared a picture book with us at the end of math class. It was called Zero, and was written by Kathryn Otoshi.

The message to the story was that we are wrong to assume that zero has no value, and that without zero our entire counting system would be completely different. I don't know about you, but I'm quite glad that we don't use a base-9 system for counting!

I remember being a young teacher and having the chance to meet the legendary constructivist math guru, John Van De Walle. He insisted, to the point of being offensive to some teachers in attendance, that we had no concept of the importance of zero to our number system. Throughout the course of an afternoon, he proved that he was right, and it was an important lesson to learn.

Building Bridges

Over the past week our class has been building bridges made out of bristle board. There was a lot of steps to this. First we had to choose what style of truss to use, there was a lot of people who chose he double warren truss.

The next step was to make a plan of what strips of bristle board we needed to make our trusses out of. After everyone was done making a plan, we all had to construct our trusses. This was the hardest step because one, we needed to hole punch the pieces, fasten them together, and make our roads.

Finally after we were all done our bridges we had to see which bridge could hold the most Lego pieces. The bridge that could hold the most pieces was able to hold 180 pieces.

Geometric "Guess Who"

For our Explore today, we played a fun variation of a very familiar game. Everyone knows how to play the game Guess Who?, and the skills involved were a perfect fit for the math lesson we were doing.

The students looked at a picture featuring many geometric shapes and chose one in their mind. Their partners then had to take turns asking "yes" or "no" questions of their partner until they correctly guessed the shape they were thinking of. Instead of asking about hair colour and whether they were wearing a hat or not, they had to base their questions on the attributes of the shapes. For instance, they had to ask questions about how many sides or vertices there were, parrallel or perpendicular lines, whether the angles were right, acute, or obtuse, or whether it had a line of symmetry.

Shape H, for example, is a six-sided shape (Hexagon) with 4 obtuse angles and 2 acute angles, it has 3 pairs of parrallel lines, no perpendicular lines, and one line of symmetry.

The students had a great time trying to stump their partners, proving once again that games can make any task educational and engaging!

Happy Pi Day!

Archimedes would have been proud of us today! Our class celebrated Pi Day in full force, and it impacted many curricular areas. After a brief lesson about pi and the relationship between a circle's circumference and its diameter, it was time for Arts Ed. We made pony bead bracelets and, when finished, we wrote as many digits of pi as would fit around our wrists.

Next it was time for math, so we made "pi plates". We took regular paper plates and measured the circumference of them using yarn. This was trickier than we thought it would be. We marked the starting point for measurement and, in teenie, tinysections, inched our way around the plate. Then we took the length of yarn and measured it to the nearest millimetre using metre sticks.

Finding the diameter was considerably easier. We folded the plates as carefully as possible and measured across the center of the plates to the nearest millimetre. The students then took their circumference and divided it by their diameter (yes - we used calculators for this!) with the hopes of getting close to pi. Most students were able to fall within the range of 2.9... and 3.5... To our amazement, two students (pictured below) were able to calculate their quotient remarkably close to pi! Their responses were 3.141... and 3.147... Amazing!

In Daily Five, we worked on writing by creating characters from the pi symbol. Being a huge baseball nerd, I created Hall of Fame Mets catcher, Mike Pi-azza. The students came up with ridiculous ideas of their own! We had Broncos quarterback Pi-ton Manning, Pi-lots, Pi-rates, Sir Pi-saac Newton, and even a Pi-rannosaurus Rex! It was too much fun!

Then it was time to listen to reading, so I did a short read aloud of Cindy Neuschwander's amazing picture book, Sir Cumference and the Dragon of Pi. The students got all of the weird math jokes and we had lots of fun with the voices of the characters!

After such a great day of pi-related activities, it was time to have a little disconnected fun. Thanks to our awesome group of generous parents, we had lots of different pies to go around, complete with ice cream and whipped cream. The students literally gorged themselves on all of the delicious pies and we crushed 4L of vanilla ice cream! Apologies to all of the parents who had to hear their children say, "I'm not hungry. Math ruined my appetite!" ;)

Before:

 

After:

 

Been there!

I am absolutely addicted to the Kid Snippet videos, but this one perfectly captures that feeling of trying to explain a math concept so many different ways that, in the end, everyone's confused!

Garbage Can Basketball

5 March 2013 - Today we took a short break from the textbook and practiced some hands-on work with fractions and decimals! We had one student away, which left us with a nice, round 25 students - an easy number to convert into 100.

Each student ripped four pages from a magazine and crumpled it up, giving us exactly 100 basketballs. I then placed a garbage can on a table at the from of the class and we were good to go. We each took 4 shots while seated at our desks, and 11 of the balls went in the bucket.

First, we wrote it as a fraction over 100. (11/100) The students then had to convert it to a decimal (0.11) and a fraction using a denominator of 1000 (110/1000) and a decimal value to the thousandths place (0.110).

Then, we established a foul line in the center of the class and the students took turns shooting four shots again. This time, 18 shots went in, so we wrote the same four values.

 

18/100 = 0.18 = 180/1000 = 0.180

Then we made it a little more challenging, each taking four shots from the back of the room. This time, only 2 went in.

2/100 = 0.02 = 20/1000 = 0.020

To finish up, Mr. C. (Grade 8 teacher) and I faced off, taking ten shots each. He hit 2, while I hit <cough> zero. The students calculated his results as:

 

2/10 = 20/100 = 0.2 = 200/1000 = 0.200

What a fun way to practice fractions and decimals!

Jellybean Fractions

February 25th, 2013 - We have been working a lot with fractions in our current math unit. in particular, we have been working with writing equivalent fractions. Today, we decided to make things a little more fun by ditching the base 10 blocks and using jelly beans instead.

Each group was given a cup of jelly beans (no, I didn't count them out first). Their first task was to count the beans to determine how many there were in total, as this would be their denominator. They then had to sort the jelly beans by colour, using each value as their numerator in a new fraction. For instance, if a group received 72 jelly beans in total, and 15 were pink, they could write this as 15/72. They did this for each of the five colours of jelly beans.

Once the beans were sorted and the fractions were written, the students had to write two equivalent fractions for each one. Whenever possible, I encouraged the students to use division to reduce their fractions. In the example above, both 72 and 15 are divisible by 3, so they could write a new fraction like 5/24. This was not always possible, however, and some groups had a denominator which was a prime number, so they had to turn to multiplication instead. Some of our denominators became quite large as a result! This wasn't a bad thing, however, as it was further support for the concept that the overall ratio of any colour does not change no matter how many pieces you cut each one into.

The students had fun working with an unexpected manipulative, and did a little pigging out at the end of class!