Saturday, March 28, 2015

Fraction Tutorials

We recently finished a unit on fractions that covered; adding, subtracting, multiplying, and dividing fractions. Fractions can be tricky things, and this was probably the most challenging math unit of 5th grade.

To help us review and remember some of the more challenging operations, a few students made tutorials, below, highlighting strategies for multiplication and division of fractions. (Other tutorials are still in the works!)

Dividing a fraction by a whole number (by Mia):

*

Dividing a whole number by a fraction (by Maya):

*

Dividing a fraction by a whole number (by Chloe):

*
Hopefully these tutorials will help you understand and solve fraction operations!

Thursday, March 12, 2015

Pi Day Challenge

March 14 is Pi Day because the date is 3/14, and those are the first three digits of the number pi (3.141592653....) This year, however, is a special Pi Day because the calendar will read 3/14/15 - the first five digits of pi!


Pi

Pi is an irrational number (it has an infinite number of digits) that is very important in many mathematical equations. 

The use of pi is a little beyond what we have been learning in 5th grade math, but I'm going to give an optional challenge relating to pi due to the special significance of this year's Pi Day. 

You do not have to do this challenge, but if you do, you may have the chance to win your very own box of Popin' Cookin'! Mmm, mmm!
(Why Popin' Cookin'? I don't really know... But there will almost certainly be some circular edibles in each box.)

You can have help with this challenge and you can look up videos or other resources to help you. You just need to be able to explain how you got the answers to me in person.

Here are the challenge questions (and a link to them as a Google Doc):


  1. What does the diameter of a circle measure?
  2. What does the circumference of a circle measure?
  3. If the diameter of a pizza is 12 inches, what is the circumference of the pizza? (Round to the nearest 100th.)
  4. If the radius of a pumpkin pie is 4 inches, what is the circumference of the pie? (Round to the nearest 100th.)
  5. What are two big discoveries that were made because of people’s understanding of pi?



Here are some resources to help you with the challenge:
  • Pizza Pi: An interactive that teaches the equations for finding the circumference and area of circles.
  • This animated gif shows how the diameter of a circle is related to its circumference (there are a little more than 3 diameter lengths in the circumference of any circle.)
"Pi-unrolled slow" by John Reid & Arpad Horvath - Image:Pi-unrolled-720.gif. Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Pi-unrolled_slow.gif#/media/File:Pi-unrolled_slow.gif
*

The challenge is due Wednesday, March 18th.
Good Luck!