Dinner time is the perfect time for conversations and a great opportunity to engage with your children. The idea of Dinner Time Maths is to add a small spark of maths to the conversation. Discuss a mathematical idea as a family or solve a problem together.

Tonight’s conversation comes to us via figurethis.org. A great place to find some fun family maths challenges. All you need is a bowl of yummy popcorn and a couple pieces of A4 paper. You can make two cylinders (or tubes) using two separate A4 pieces of paper. Roll one into a short cylinder and the other into a tall cylinder. Ask your children, which cylinder will hold more popcorn? Let everyone estimate and guess and then experiment to find the answer.


A great hint offered on figurethis.org is to place the tall cylinder inside the short one. Fill the taller with popcorn; then remove it from the shorter one, allowing the popcorn to fall into the shorter the cylinder.

This process clearly shows that the shorter cylinder holds more. For a more detailed solution visit figurethis.org.

In national testing and even in IQ tests, it is the ability to visualise two and three dimensional space that people find most challenging. As with all skills, some are born with a more natural aptitude than others, but everyone can learn to develop them. Comparing the volume of different sized containers is a great way to develop these skills.

Our inspiration for Dinner Time Maths comes from Laura Bilodeau Overdeck who is the brainchild of Bedtime Math, a brilliant blog dedicated to providing you with ideas to incorporate a maths problem into every day.

Photo credit: davidsilver / Foter.com / CC BY-NC-SA