Posted in Elementary School Math, Math videos, Number Sense

Why PEMDAS is ‘morally’ wrong

Here’s a video that explains why you need to memorise PEMDAS (or BODMAS, BIDMAS, depending where you are in the world) order of operation and why you don’t need to. Minute Physics who made this video made a mistake in assuming that PEMDAS is taught in schools without emphasising that multiplication and division should be done whichever comes first from left to right. But he does explain the ‘why’ behind the rule plus the importance of knowing fundamental ideas such as the distributive property and the associative property. This is what makes the video worth viewing.

You want to test your PEMDAS skill try this problem.

Posted in Geometry, Math videos

A Geometric Model for the Lunch Date Problem

geometric modelA mathematical model is an abstract model that uses mathematical language to describe and understand a situation. Here’s a nice video that presents a model for the Lunch Date Problem. The video below shows a step-by-step tutorial using SketchPad to build a geometric model of the problem. What is nice about this video is that it still leaves the solving to the students. The resulting geometric model leaves enough information for students to figure out a solution.

The Lunch Date Problem

You and a friend arrange to meet between 12:00 and 1:00 in the afternoon. After a week neither of you remembers the exact meeting time. As a result, it is possible for you arrive at random between 12:00 and 1:00 and waits exactly 15 minutes for your friend to arrive. After 15 minutes, each of you leaves if the other person has not arrived. What is the probability that the two of you will meet?

Mathematical modelling involves the use of mathematics to understand a real world problem. Click What is mathematical modelling? to learn more about it.

 

Posted in Math videos, Number Sense

911 math assistance service

A four-year old calling 911 for math assistance.

History tells us that zero was invented much later than most of the numbers. It was not even accepted as a number right away. Why should we expect a four-year old to think of it then? And take-aways without context for them?

Anyway, this video is cute. The police has some teaching skill. Enjoy it.

Posted in Math videos

A 21st century skill: reading and writing codes

In Should We Do Away with Calculation, Conrad Wolfram says that if you want to know if students understands a computational procedure, ask them to do a program, let them code it.Here is another video which calls students to learn coding. The video titled What Schools Don’t Teach featuring Bill Gates, Mark Zuckerburg, and other software developer giants speaking, urges kids to learn how to write codes. Reading and writing codes should now indeed be part of our curriculum. And for the arts inclined? Well to borrow from WordPress: ‘Code is poetry’.

What schools don’t teach video promotes code.org, a nonprofit foundation created to help computer programming education grow.

To drive the point, see the graph below from code.org.

computer programming