OMG! Credit Card Antenna Geometry is so cool + some PIN Probability

January 24, 2023

The world  has mostly agreed on the size of a credit card:

Credit cards today contain a microchip and aerial.

A credit card is dissolved in ACETONE (solvent found in some nail polish removers) to extract the chip & aerial in this BBC video.


OMG! It still works to pay for coffee but if you wanted cash you would still need the PIN.


How to Teach Maths … funny … funny … funny … BBC 4 Podcast

January 14, 2023

The BBC 4 THE INFINITE MONKEY CAGE podcast How to Teach Maths hosted by Brian Cox and Robin Ince is soooo funny and informative. This is not just for Maths lovers. Included on the panel are comedian Sara Pascoe and the very numerate Prof Hannah Fry, maths comedian Matt Parker and statistician Prof David Spiegelhalter. 

It is worth listening to Prof Brian Cox say he wasn’t so good at maths at school. But he loved PHYSICS. Prof Cox studied as a mature age student!!!!!!!!!

Find Podcast here:



How to TEACH MATHS TUNEin here

How to TEACH MATHS Apple Podcasts here


MOZZIE MATHS: How much blood do those little blood suckers suck?

December 9, 2022

You can learn almost everything you need to know about mosquitoes from this article on:

The Conversation.


Dangerous Math: Death by Snake, Spider, Quad bike, Kangaroo, Raccoon and Vomit

November 17, 2022

It’s almost summer in Australia. In Melbourne we’ve had floods, mosquito – mozzie- numbers surge and, last Wednesday, I nearly stood on a Tiger Snake that was escaping the floods near the Yarra River! 

This post, however, is really a PR exercise for sharks. We fear them. We’re horrified by the thought of being eaten alive!!!. We only have to hear the soundtrack from JAWS to feel the fear. Then we see news footage like the attack below and think it happens all the time. Look at that fin. It’s enormous! But sharks are not THAT dangerous. We really need to look at the statistics to understand the level of threat. See below.

Why do we fear sharks? Look at the numbers. REALLY. Show your students. What about stairs??? Quad bikes? Chairs? Bees? That’s when you should feel the fear!!! We are irrational beings. This is why we need maths. We can make rational decisions using maths. There is also a safety message here. The maths speaks for itself. We won’t hammer it.


There is lots of maths you can do with these tables.

  • Bar Graphs
  • Pie Charts
  • Ratios (What’s the ratio of death by Snake to Quad Bike?)
  • Fractions (Show death by jet ski to falling down stairs as a fraction)
  • Percentages
  • Powers to the base 10. How many deaths occur in each country per 100,000 or 1 x 10head of population for, say, Quad bikes or ATVs? We can use these numbers to compare death rates and find out how dangerous riding a Quad bike is in each country.

……..Population Data 2022

……..Aust…26 million = 26 x 106

……..USA…332 million = 332 x 106

……..Canada…38 million = 38 x 106

……..UK…67 million = 67 x 106

But we’re doing this for the SHARKS!!! Death Australia Mathspig

  1. Cyclists. 2. emergency lanes 3. fell off a chair 4.QUAD BIKES. 5. Horse, donkey. 6. buses 7. Cow, bull. 8. ice skates, skis or skateboards. 9. Venemous snake 10. kangaroo 11. bee 12. emu 13. Jet ski 14. Shark 15. Crocodile

Death USA Mathspig 21. Quad Bike or ATV: In 2007, 107 children younger than 16 were killed on ATVs. 2. Cyclists 3. choke on vomit  4. Cats, cows, horses, pigs, raccoons. 5. Bees, wasps  6.PWC or Jet Ski 7. Lightning 8. Xmas tree fires 9. Snowboard 10. Venomous Spider  11. Scorpions 12. Venomous Snakes , lizards. 13.Crocs & gators  14. Shark Death Canada Mathspig

  1. ATV Quad Bike 2. Canoe  3. Kayak 4. PWC or Jet Ski  5. Unpowered inflatable 6. Avalanches or landslides. 7. Lightning 8. Toboggan 9. Moose –Car collision 10. Bears (All Nth America) 11. Rattle Snake 12. Wolves 13. Shark

Death UK Mathspig

  1. falling down stairs.  2. Cyclists.  3. Choke on vomit   4. Falling off Chairs 5.  QUAD BIKE or ATV 6. Buses 7. Struck by cow, horse, other mammal 8. hornets, wasps, bees. 9. PWC or jet ski .10. Parachutists. 11. Skateboards, ice skates, skis 12. Canoe. 13. Shark 

Halloween Math: Witches vs Zombies 2

October 16, 2022



Halloween Math : Witches vs Zombies 1

October 16, 2022

There has been a real world Witches Vs Zombie Fight.

The witches of the Haunted House in Salem, Massachusetts, are at war with the Zombies of The Nightmare Factory nearby. A witch tripped a Zombie who was wearing a straight jacket!!!! And … read it for yourself in the Daily Mail, UK.

Links: Top Grossing Horror Movies

Blair Witch Project Budget here.


Real World Maths: Surds and all that jazz …

October 12, 2022

Eddie Woo is an Aussie Maths teacher who runs his own Youtube Channel. So popular is this channel in October 2015, Woo won the NSW Premier’s Prize for Innovation in Science and Mathematics. This youtube clip won’t tell you where you will use surds, but it does something magical.

It compares surds to different kinds of music to help students understand why mathematicians go crazy over the concept of surds. This clip tells why maths is soooooo special. There is no guesswork or fake information in this maths. Maths must be accurate. And surds demonstrate this point. (Look for the 5 min mark)

Will you use surds in real life?

Maybe. Probably, not. But surds are used in mathematical programs that demand accuracy. eg. engineering skyscrapers, building satellite dishes, and even in video games. But you won’t see them. Like so much mathematics surds will be hidden in some algorithm.

Here are two Examples:

1. The Golden Ratio:

Often written a 1:1.61 the Golden Ratio or Fibonacci Sequence appears in art and nature and has an aesthetic appeal to the eye, but the accurate ratio is:

2. The Quadratic Function

Satellite dishes, headlights, torches, and bridges all designed using the parabolic arc. The parabola is defined by the quadratic function and sometimes solving for x produces an irrational no. namely a surd. Rounding off can introduce inaccuracies that can become more dramatic when scaled up to the sie of, say, a bridge. 

3. The Golden Ratio in Music

Mozart arranged his piano sonatas so that the number of bars in the development and recapitulation divided by the number of bars in the exposition would equal approximately 1.618, the Golden Ratio. Find more @ CLASSIC FM.

Back to Mozart.

In the above diagram, C is the sonata’s first movement as a whole, B is the development and recapitulation, and A is the exposition.

And here is Mozart’s Piano Sonata No. 1 in C Major as an example. Can you hear the Golden Ratio. Not really. But it’s there.


DART vs ASTEROID: Middle School Math

September 27, 2022

DART is a test

of NASA’s planetary defence plans.



                                       Guess what?

The DART(Double Asteroid Redirection Test) mission was launched on Nov. 23, 2021, atop a SpaceX Falcon 9 rocket from the Vandenberg Space Force Base in California.

It is the size of a small vending machine and it has been travelling through space for 10 months.


Outdoor Maths Adventures: Middle School

September 16, 2022

As the weather improves – Spring in Melbourne, my city & Fall in USA & Autumn in the UK – it is an ideal time to take math outdoors. Here are some fab exercises for Middle School Math.

Outdoor maths middle school 1 mathspig

Lego Man soccer fields will vary in size depending on the height of each player picked by each student. This does your head in. It is really challenging maths!


Outdoor Maths Middle School 2 Mathspig

McGill Uni link here.

Outdoor Maths MIddle School 3 Mathspig

Don’t forget to throw in Mathspig’s lame protractor jokes.

Outdoor Maths Middle School 4 mathspig

You’ll find full calculations at the Maths is Fun blog.

Outdoor Maths Middle School 5 Mathspig

You’ll find more fab outdoor junior and middle school maths activities at the terrific Maths and Movement blog.

Outdoor Maths Middle school 6 Mathspig

Some students will discover their co-ordinate point is not on the grid. Students should then work out that they will need a different scale for the y-axis. You can get more inspiration at the Stand Again blog.


Outdoor Math Adventures: Grade 3 – 5

September 16, 2022

It’s Autumn in UK & FALL in the USA so it’s the perfect time for a little bit of outdoor math for Grade 3-5 with AUTUMN leaves. Of course, you don’t need FALL LEAVES for this exercise, but it is colorful.
Outdoor Maths 1 Mathspig 2

This fab idea comes from Juliet Robertson, an outdoor education consultant in Scotland. Her blog Creative star learning is one of the most inspiring outdoor maths blogs you will find.

Outdoor Maths 2 Mathspig

Outdoor Maths 3 mathspig

Outdoor Maths 4 Mathspig

Outdoor Maths 5 Mathspig

Outdoor Maths 6 Mathspig

Outdoor Maths 7 Mathspig

Outdoor Maths 8 Mathspig

Check out Mathpig’s protractor joke here.

Outdoor Maths 9 Mathspig

Outdoor Maths 10 Mathspig

Another fab idea from Juliet Robertson.