"What happens when you heat a particle up?" University of Pretoria (UP) nuclear physicist Dr Thabsile Thabethe asks her two-year-old daughter.
Her little girl starts running around as she learns that a hot particle moves quickly.
"And what about when it's cold?"
Her daughter does a slow-motion walk and stage whispers: "It goes slowly mama."
These are some of the ideas that 30-year-old Thabethe has put into her series of books – Thermodynamics for Babies and Toddlers; Biology for Toddlers: Body Parts and their Function; Introduction to mathematics for toddlers: Addition; and Introduction to mathematics for toddlers: Subtraction.
Self-published to see how well they will be received, and available to order on Amazon, the books are creating excitement among parents whose own knowledge of the topics is a bit fuzzy.
Thabethe tells News24 that in between her own post-doctoral studies and lecturing at UP, she has always squeezed in games and conversations about numbers and science when she is with her daughter.
In the early days, when she was teaching her little muse numbers, she wanted to make sure she truly understood them, and that she was not just reciting them or memorising their shapes.
She explained that she would put two balls on a table and ask her daughter to count them. Her daughter would reply "Two!" and she would add one more, with the funny faces and animated body language that would have her daughter saying "Three!" and they would do it again.
"At that young age they like anything that is colourful, anything that sounds amazing and wow. Especially when you do faces and you're like 'That's two! Can you do it?'"
The seed for the book idea was planted after she Googled age-appropriate science books for her daughter who could count to 10 by the time she was 18 months old.
She found books on the Pythagorean theorem for toddlers for example, but discovered that most of them did not include the basic concepts such as addition and subtraction that are embedded in the understanding of the topics.
Other science books for toddlers would simply have a picture with one scientific word, leaving it up to the person reading to the toddler to fill in the gaps and explain.
Realising that not every child has two physicist parents like her daughter, she decided she would start developing her own science stories for her child.
One of the sections in Thermodynamics for Babies and Toddlers focuses on what a thermometer is and how temperature is measured.
"So when you talk of heat, you are talking of energy," she explains.
"If you are in a room right now, the room is quite cool. You can use the thermometer to measure the temperature of the room. And then from there you take a hot cup, you put a hot cup [on a counter].
"The cup now is hot, but the room is cold.
Limit activities to avoid boredom
"You go outside for a long time, maybe to the shop, and by the time you come back, you will find that the cup and the water inside are cool.
"How does it happen? And that's where I explain that the cup moves its heat into the air in the room. That is energy."
There is a lot of play with mum holding a small bowl showing how a molecule moves, and the two of them running or shuffling, pretending to be hot or cold molecules, while the book guides the reader through the terminology and why everything is happening the way it is.
Hence the darting around the kitchen pretending to be a hot particle.
"And that is basically it. We have basically actually defined kinetic molecular theory," she says.
Thabethe adds that she limits the activities in the books to five minutes to avoid boredom or being overwhelmed and mixes things up with some word matching and even reading scientific and mathematical symbols.
While she is doing this, things do not grind to a halt in the home. The soapies are on in the background, her daughter is in her Elsa jammies, pootling around with a snack, so that it is not seen as a big deal.
And when she is not reading about physics, or numbers, the tiny tot loves all the usual childhood books, with Terrible Tiger being her current favourite.
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