Archive for the ‘Junior School’ Category


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 

How BIG is Australia?

June 19, 2022

There are 26 million people in Australia.


No Frills MATHs Skills for Parents 4: FRACTIONS for Beginners

June 6, 2022

Here is a post on Lego Fractions by New York Grade 3 teacher Alycia Zimmerman. Surprisingly I found this on an art website.



Just play with the Lego blocks. Add and subtract … you can even multiply and divide.

Next time.


No Frills MATHs SKILLS for Parents 3: Pre-Algebra

May 23, 2022


Killer Easter Egg Math

March 30, 2022

According to The Guinness Book of Records the largest chocolate Easter Egg went on display at Le Acciaierie Shopping Centre, in Cortenuova, Italy, on 2011.

 Egg Weight   = 7,200 kg  = 15,873 lbs

Height = 10 m =  34 ft

Circumference = 19.6 m = 64 ft

The sugar content for easter eggs is: 55-65% by weight

So we will assume the sugar content of the giant egg was in the middle:


The weight of sugar in the giant egg equals:


What’s the Maths Curriculum got to do with it? WHEN Maths is, like, soooo BORING!!!!!

February 22, 2022

Australia is reviewing its Maths Curriculum.

Sides are taken. Arguments are rife. See the excellent article by Donna LuCracking the formula: how should Australia be teaching maths under the national curriculum?, The Guardian,13 FEB, 2022)

Should teachers teach? Or students explore problems? (Called Cognitive Activation in academe!)

Why not, both? Then add outdoor maths (below) plus defronting the classroom sometimes and try some maths selfies for homework. More ideas here

It doesn’t matter what’s written in the curriculum, the biggest problem in maths for students is


Here, to tackle boredom are:

41 Maths things to do before you’re 12

Mathspig outdoor play quote

mathspig outdoor-play-app

A growing body of research shows us that outdoor play leads to better physical and mental health, has positive effects on cognitive function and learning, and reduces the incidence of behavioural problems.” Maria Zotti, Nature Play, SA.

Peter Dunstan, Principal Kilkenny PS, SA, writes in SAPPA magazine, Primary Focus, that outdoor play fosters “wonderment, independence and freedom” as well as “social skills, imagination, creativity and problem solving”.

Inspired by SAPPA and NaturePlay,  Mathspig has produced her own outdoorsy maths list:

 Mathspig 41 maths things 1Mathspig 41 maths things 2mathspig 41 maths things 3

Mathspig 41 maths things 4mathspig 41 maths things 5


7. Robin Hood Give us your best shot.

9. You can measure the volume of your lungs by blowing one breath into a balloon and pushing it into a full bucket of water. Measure the overflow.

15: Outdoor Maths: Times Tables

21. Light intensity links. Here and here.

25.  Sound Volume Measurement

36. Killer heels that really kill.


NATHAN CHEN wins Gold but Figure Skating Scores can be BAD MATH

February 10, 2022

Nathan Chen, 22, USA, wins GOLD in the Men’s Figure skating with 5 brilliant, soaring quadruple jumps executed to perfection to Elton John’s “Goodbye Yellow Brick Road” and “Rocket Man.”

Nathan Chen’s Winning Performance on You tube HERE.

According to the fab NBC video, Mathletes,  nine Figure Skating judges score competitors for the complexity of each element (eg. Triple axel or triple spin jump) and the quality of the performance producing a score out of ten.

Tessa Virtue and Scott Moir(Above) GOLD Medal performance at Pyeongchang 2018 here.

Kailani Craine, Australia

figure skating score 9 judges nbclearn

This is a typical figure skating score card for one competitor.

The final score, however, is based  on the average for only 5 of these scores. Two are eliminated by random selection (Red Brackets). Then the top and bottom scores are removed and the remaining five scores averaged.

Screen grab NBC Mathletes

Screen grab NBC Mathletes



of Skater A & B:

figure skating score A

Skater A:

Four scores are removed. Two by the random selector (in brackets) and then the top and bottom scores (with line drawn through them)

7.00 + 7.00 + 7.00 + 6.75 + 7.00


=  34.75/ 5 = 6.95

figure skating score B

Skater B:

Four scores are removed. Two by the random selector (in brackets) and then the top and bottom scores (with line drawn through them). But this time the random selector eliminates two low scores.

The average:

7.00 + 7.25 + 7.00 + 7.00 + 7.00


=  35.25/ 5 = 7.05

Same score cards but Skater B gets a higher average score than Skater A.

Skater A is, in fact, beaten by a random number selector!!!!


Sound Math 2: Can you hear this high pitch sound?

September 30, 2021

One of the best summaries of sound can be found here at Maths is Fun

Sound from 0-1000000 Hz in one minute(below)

Other Sound Math:

Make a match Box sing like Sinatra

The Curious Nature of Drummers’ Brains

Headbanger Maths

Pump Up the volume or Knock, Knock Knockin on Your skull wall!


Sound Math 3: How loud is LOUD?

September 29, 2021

The logarithmic equation for sound and the decibel calculator here

More here

Other Sound Math:

Make a match Box sing like Sinatra

The Curious Nature of Drummers’ Brains

Headbanger Maths

Pump Up the volume or Knock, Knock Knockin on Your skull wall!


Sound Math 4: Make a match Box sing like Sinatra

September 29, 2021

Other Mathspig Sound Posts:

The Curious Nature of Drummers’ Brains

Headbanger Maths

Pump Up the volume or Knock, Knock Knockin on Your skull wall!