Science! (for toddlers)

I’m not sure that there’s any age that’s too-young at which to try to cultivate an interest in science. Once a child’s old enough to ask why something is the case, every question poses an opportunity for an experiment! Sometimes a thought experiment is sufficient (“Uncle Dan: why do dogs not wear clothes?”) but other times provide the opportunity for some genuine hands-on experimentation (“Why do we put flowers in water?”). All you have to do is take every question and work out what you’d do if you didn’t know the answer either! A willingness to take any problem with a “let’s find out” mentality teaches children two important things: (a) that while grown-ups will generally know more than them, that nobody has all the answers, and (b) that you can use experiments to help find the answers to questions – even ones that have never been asked before!

Annabel sorts jewellery at the Pitt River Museum of Anthropology.
“Why do we make jewellery out of different things?” Thanks to the Pitt Rivers Museum for inspiring this question… and helping us to find an answer.

Sometimes it takes a little more effort. Kids – like all of us, a lot of the time – can often be quite happy to simply accept the world as-it-is and not ask “why”. But because a fun and educational science activity is a good way to occupy a little one (and remember: all it needs to be science is to ask a question and then try to use evidence to answer it!), I’ve been keeping a list of possible future activities so that we’ve got a nice rainy-day list of things to try. And because we are, these days, in an increasingly-large circle of breeders, I thought I’d share some with you.

Annabel observes the filling of a paddling pool with custard.
You don’t strictly need a cement mixer full of custard to demonstrate dilatant (non-Newtonian) fluids, but messiness is engaging all by itself.

Here’s some of the activities we’ve been doing so far (or that I’ve got lined-up for future activities as and when they become appropriate):

  • Measuring and graphing rainfall
    We’ve spent a lot of time lately taking about calendars, weather, and seasons, so I’m thinking this one’s coming soon. All we need is a container you can leave in the garden, a measuring jug, and some graph paper.
  • Experimenting with non-Newtonian fluids
    You can make a dilatant fluid with cornflower and water: it acts like a liquid, but you can slap it and grab it like a solid. Fine, very wet sand (quicksand!) demonstrates pseudoplasticity which also explains how paint ‘blobs’ on your brush but is easy to spread thin on the paper.
  • Magnets
    I’m really looking forward to the opportunity to play with magnets: we’ve started already with thanks to Brio wooden railway and talking about the fact that the rolling stock will attach one way around (and seem to jump together when they get close) but repel the other way around, and we’ve also begun looking at the fact that if you remove a carriage from the middle of a train the remaining segments are already correctly-aligned in order to be re-attached.
  • Different kinds of bouncy balls
    We’ve had fun before measuring how high different kinds of balls (air-filled rubber football, large solid rubber ball, skeletal rubber ball, small solid rubber ball) bounce when dropped from a stepladder onto a patio and talking about how ‘squishy’ they are relative to one another, and speculating as to the relationship between the two.
Red-spotted black ladybird.
Spotting different subspecies of ladybirds is a great springboard to talking about heritable characteristics and phenotypic variation. Snails are another good candidate.
  • Demonstrating capillary action/siphoning
    Two containers – one with a fluid in and one without – joined over the rim by a piece of paper towel will eventually reach an equilibrium of volume, first as a result of capillary action causing the fluid to climb the paper and then using a siphon effect to continually draw more over the edge.
  • Illustrating the solar system (to scale)
    It helps adults and children alike to comprehend the scale of the solar system if you draw it to scale. If you’ve got a long street nearby you can chalk it onto the pavement. If not, you’ll need a very small scale, but doing the Earth and Moon might suffice.
  • Electricity
    Batteries, wires, and LEDs are a moderately safe and simple start to understanding electricity. Taking a ‘dead’ battery from a drained toy and putting it into the circuit shows the eventual state of batteries. Connecting lights in series or parallel demonstrates in very simple terms resistance. Breaking or joining a circuit illustrates that switches function identically wherever they’re placed on the circuit.
  • Vortices
    I’m interested in trying to replicate this experiment into making different kinds of standing vortices in water, but I might have to wait until our little scientist has slightly more patience (and fine motor control!).
A demonstration of capillary action using water and tissue paper.
Water, tissue paper, and patience is all you need to demonstrate capillary action and siphoning. Food colouring’s an optional bonus.
  • Centripetal force
    We’ve been lucky enough to get to talk about this after using a whirlpool-shaped piece of marble run, but if we hadn’t then I was thinking we’d wait until the next time it was sunny enough for outdoor water play and use the fact that a full bucket can be spun around without spilling any in a similar way.
  • Bug counting
    Take a quadrant of garden and count the different kinds of things living in it. Multiply up to estimate the population across the garden, or measure different parts (lawn versus bedding plants versus patio, direct sunlight versus shade, exposed versus covered, etc.) to see which plants or animals prefer different conditions.
  • Growing plants
    Caring for different kinds of plants provides an introduction to botany, and there’s a lot to observe, from the way that plants grow and turn to face the light to the different stages of their growth and reproduction. Flowers give an attractive result at the end, but herbs and vegetables can be eaten! (Our little scientist is an enormous fan of grazing home-grown chives.)
  • Mechanics and force
    We’ve taken to occasionally getting bikes out of the shed, flipping them upside-down, and observing how changing the cogs that the chain runs over affects how hard you need to push the pedals to get movement… but also how much the movement input is multiplied into the movement of the wheel. We’re not quite at a point where we can reliably make predictions based on this observation, but we’re getting there! I’m thinking that we can follow-up this experiment by building simple catapults to see how levers act as a force multiplier.
Annabel and Ruth cooking.
Cooking provides opportunities for exploration, too. Bake some bread and you’ve got an excuse to talk about yeast!
  • Chromotography of inks
    I’ve been waiting to do this until I get the chance to work out which felt tip pens are going to give us the most-exciting results… but maybe that’s an experiment we should do together, too! Colouring-in coffee filter papers and then letting them stand in a cup of water (assuming a water-soluable ink) should produce pretty results… and show the composition of the inks, too!
  • Colour mixing
    Mixing paint or play-doh is an easy way to demonstrate subtractive colour mixing. We got the chance to do some additive colour mixing using a colour disk spinner at a recent science fair event, but if we hadn’t I’d always had plans to build our own, like this one.
  • Structure and form of life
    Looking at the way that different plants and animals’ physical structure supports their activities makes for good hands-on or thought-driven experimentation. A day at the zoo gets a few steps more-educational for a preschooler when you start talking about what penguins are able to do as a result of the shape of their unusual wings and a walk in the park can be science’d-up by collecting the leaves of different trees and thinking about why they’re different to one another.
  • Stabbing balloons
    The classic magic trick of poking a skewer through a balloon… with petroleum jelly on the skewer… lends itself to some science, so it’s on my to-do list.
Paining a colour wheel.
Subtractive colour mixing can be demonstrated by mixing paint. Colour and spin a wheel to demonstrate additive mixing.
  • Surface tension
    Water’s such a brilliant chemical because it’s commonplace, safe, and exhibits so many interesting phenomena. Surface tension can be demonstrated by ‘floating’ things like paperclips on top of the surface, and can be broken by the addition of soap.
  • Astronomy
    In the winter months when the sun sets before bedtime are a great time to show off stars, planets, satellites and the moon. Eyes or binoculars are plenty sufficient to get started.
  • Life cycles
    I was especially pleased when our nursery kept an incubator full of chicken eggs so that the children could watch them hatch and the chicks emerge. We’d looked at this process before at a farm, but it clearly had a big impact to see it again. Helping to collect eggs laid by my mother’s chickens helps to join-up the circle. Frogspawn and caterpillars provide a way to look at a very different kind of animal life.
  • Putting baking soda into things
    Different everyday kitchen liquids (water, vinegar, oil…) react differently to the addition of baking soda. This provides a very gentle introduction to chemistry and provides an excuse to talk about making and testing predictions: now that we’ve seen what cold water does, do you think that hot water will be the same or different?
Annabel is awed by the size of a tyrannosaurus rex skeleton.
“Why do some animals have sharp teeth and some have flat teeth?” was a question I posed. We found the answer together (and were wowed by the size of the T-rex skeleton behind the camera) at the Natural History Museum.
  • Bubbles and foams
    Blowing bubbles through different types of mesh (we just used different kinds of tea towels elastic-banded to the cut-off end of a plastic bottle) demonstrates how you can produce foams of different consistencies – from millions of tiny bubbles to fewer larger bubbles – because of the permeability of the fabric. And then we wrecked the last tea towel by adding food colouring to it so we could make coloured foams (“bubble snakes”).
  • Phase transition
    Start with ice and work out what makes it melt: does it melt faster in your hand or in a dish? Does it melt faster or slower if we break it up into smaller parts? If we ‘paint’ pictures on the patio with them, where does the water go? I’m also thinking about ways in which we can safely condense the steam (and capture the vapour) from the kettle onto e.g. a chilled surface. Once we’re at a point where a thermometer makes sense I was also considering replicating the experiment of measuring the temperature of melting snow: or perhaps even at that point trying to manipulate the triple point of water using e.g. salt.
  • Dissection
    Take apart the bits of a flower, or look in detail at the parts of a bone-in cut of meat, and try to understand what they’re all for and why they are the way they are.
  • What floats?
    Next time the paddling pool is out, I’d like to start a more-serious look at which things float and which things don’t any try to work out why. What might initially seem intuitive – dense (heavy-for-their-size) things sink – can be expanded by using plasticine to make a mixture of ‘sinking’ and ‘floating’ vessels and lead to further discovery. I’m also thinking we need to do the classic ‘raisins in a fizzy drink’ thing (raisins sink, but their rough surfaces trap the bubbles escaping from the now-unpressurised liquid, causing them to float back up to shed their bubbles).
Annabel hugs a goat.
Get some hands-on biology at your nearest petting zoo. No science in this picture, but plenty of hugging.

So there’s my “now and next” list of science activities that we’ll be playing at over the coming months. I’m always open to more suggestions, though, so if you’re similarly trying to help shape an enquiring and analytical mind, let me know what you’ve been up to!

 

Pen testing

This is not a blog post about pentesting, or any other kind of software-engineering inspired testing of pens. Nor is it a blog post about the kind of fascination some people have with pens and ink. Instead, this is a blog post about history and psychology.

Recently, JTA asked me what I do when I want to test a pen, and he was surprised with the answer. Before I tell you how I answered, I’ll tell you about what I learned from the conversation. And before that, I’ll tell you about the history of pen testing. And then, finally, I’ll tell you why I think it’s important from a psychological perspective.

Fragment of the Hebban Olla Uogala document, the oldest surviving Probatio Pennae.
The oldest surviving Probatio Pennae, or “pen test”, is of the Old Dutch words “hebban olla uogala”, and is stored in the Bodleian Library.

Historically, the “breaking in” of a new pen was called a probatio pennae, literally “pen test”, and would typically be a few lines of text or a short proverb: something that demonstrated the pen’s ability to write. For the entire mediaeval period, plus several centuries besides, the principle instrument for writing would be the quill pen: the primary wing feathers of a large bird such as a goose, often hardened in hot ashes, stripped of barbs, and cut down to size with an blade whose purpose lends its name to what we now call a “pen knife”. With such a tool, a scribe would want to be sure that the pen could hold an adequate nibful of ink without splashing or spraying, and – despite the high value of paper – it was clearly essential to write a whole sentence or two to be sure.

De Klerk, by Philip van Djik.
De Klerk, by Philip van Djik, contemporaneously shows a scribe cutting the nib of his quill pen.

A modern ballpoint pen has no such issues, but instead introduces some of its own: a plastic-lined inkwell can be gradually penetrated by the air, causing the ink to dry up; the ball can become stuck and will not turn freely; air bubble can develop within the tube (especially if the pen is stored, or worse-still used, the wrong way up); and, of course, the pen can run out of ink. This typically precipitates its disposal: your biro isn’t built to be re-used for anything except perhaps to perform an emergency tracheotomy, and it’s cheap enough that you don’t want to waste your time repairing it. As a result, our pen tests have become fast, designed to determine within a few seconds whether the pen we’ve got is working or, in the case of a stuck ball, can be made to start working with a sufficiency of scribbling. Our culture of disposal can’t spare the time for any more than a cursory test before we give up and grab the next one.

Comic: A customer stands confused, holding a toaster, outside Melvin's Throw-It-Away-And-Buy-A-New-One-Shop (formerly Melvin's Fix-It Shop)
Why keep a pen? Why keep a toaster? Why keep a computer?

So what do we write? What is the probatio pennae of our times? It’s been widely-reported (although I can’t find any decent citations) that, upon being offered a new pen to try out, 97% of people will write their own name. Now that statistic smells fishy to me (no good citations anywhere, and 97% of people use 97% as their “virtually all” number, for made-up statistics), but I’ve been testing the hypothesis among friends these last few days, and I’ve gathered enough evidence to convince me that it’s probably the case that many or most people will write their own name to test a pen.

Signing a cheque.
That’s not so surprising: in this computerised age, most times we’re given a pen it’s to sign our name. About 97% of the time, anyway. ;-)

Somebody had presumably asked JTA what he wrote, earlier in the day, because he took the time to tell me that when he tests a new pen, he typically writes the word “hello”.

Now I find that pretty weird. Maybe it’s the software engineer in me, but to me the mark of a good test is that it covers all of the possible cases, in the minimal possible effort. Writing your name is easy because it’s managed by what is popularly-called “muscle memory”: a second-season episode of Castle (correctly) used this as a plot point, when a man suffering from retrograde amnesia was unable to remember his name, but was still able to sign his name because the act of signing it had been rendered, by years of practice, into his procedural memory, which was unaffected by his condition. But writing a word, like “hello”… requires a comprehension of language. Unless he’s tested enough pens to have built a procedural memory of writing “hello” to test pens, JTA’s test has a greater number of neural dependencies, which – with apologies to those of you who aren’t interested in automated software testing – produces what we’d call an unnecessarily “brittle” test.

Animation of a hand using a pen to write a name, "hello", and a scribble.
A demonstration of a handful of ways in which people test pens, in Animated GIF format.

Me? I just scribble, which my quick survey (and several comparable ones online) show to be probably the second-most popular action to test a pen. Scribbling, to me, simply seems like the minimal test path: the single simplest thing that can be done with a pen that will demonstrate that it’s fit for purpose. I don’t need to test that a new pen can write words, because – to me – writing words in particular is not a function of the pen, but a function of my brain! To me, the pen’s function is simply one of transferring ink to the paper, and any semantic meaning coming from the ink is a product of my intellect, not of the writing implement.

So why is this important? Well: I have a half-baked hypothesis that the choice of what to write with a new pen might be linked to other aspects of our psychology. When I’m developing a new template for a website, for example, I use lorem ipsum text and dummy placeholder images as filler (just occasionally, I’ll use kittens, because kittens are adorable). That’s because the absence of meaning to the words that appear (I don’t read Latin, and even if I did, lorem ipsum is frequently mangled) has no bearing on my comprehension of the design: and, in fact, it can sometimes be a benefit to be deprived of the distraction of legible content.

A kitten by a mirror.
At last, a legitimate use in an otherwise un-kitten-related blog post to use a PlaceKitten.com image!

But I’d hypothesise that people who write words as a probatio pennae would be less-comfortable with illegible placeholder-text in a design than those who drew scribbles or signed their name. I have a notion, from my own experience, that the same parts of the brain that is responsible for judging the quality of a writing implement are used in the judgement of a piece of design work. Hey: maybe if that’s true, graphic designers should have their clients test pens out, in their presence, before they decide whether to use believable filler or lorem ipsum text in the designs they’d like approved.

Or maybe I’m way off base. What do you write when you test a pen?