Archive for the ‘Kidstuff’ Category
This variation on Twenty Questions teaches kids a bit of information theory and lets them take a different approach to powers of 2.
First, the kids should be familiar with the regular game of Twenty Questions.
Then, ask as an open-ended question: “Suppose instead of the whole world. you were only allowed to think of certain objects. How many questions would it take to find the right one? What if the questions had to have only yes/no answers?”
Here is another opportunity for discovery: one-third. For kids who have learned how to divide and get decimals (or show a child briefly who has learned long division and knows what decimals are). Ask simply, what is one-third in decimal?
The discovery that 1/3 = .33333333… the repeating decimal, is surprising enough on its own for a child who has never seen an infinite series before. What usually will tweak their curiousity, though, is to continue – ok, what is 2/3? Then wait a moment, and see if they think of 3/3 by themselves. The idea that 3/3 = .999999999… may get the child saying, wait a minute – 3/3 = 1!
They have just proved that an infinite series can equal a whole number; if your child doesn’t want to accept it, that is ok. Just assure them that if the series stops anywhere, it is less than one, it only equals one if it is really infinite.
The fun thing is, this can be done by a 4th grader.
For kids who have been introduced to exponents but haven’t been taught specifically about what it means to take ‘N to the zero power’, this is an opportunity for a small ‘Aha!’ moment.
If a child already knows what is ten to the 2 (10^2 = 10 * 10 = 100) and 10^1 = 10, ask them what is 10^0.
Let them think a bit. Many kids will answer ‘zero’. Ask, well, then what is zero times 10? If its not 10^1, then that can’t be right.
Explain that 10^0 must be the thing that you multiply by 10 to get 10^1. This should be enough of a clue that they realize that 10 to the zero is 1.
Then, without any other explanation, ask something that sounds hard – “what is eighty-seven to the zeroth power?” With a bit of thought, your child may be able to come to the sudden realization that everything to the zeroth power is 1!
(This only works if they haven’t already been taught this fact in school – it is fun to discover things that no one has told you. So don’t be afraid to try this somewhat early, before most schools cover it.)
Here is a fun way to introduce kids to the concept of modulus (without ever saying the word): ask, why does a week have 7 days? Suppose you could change it – how many days would you put in the week? Then ask some questions about ‘in X days, what day would it be?’
It helps to ask the child to consider the days as being named by number at first, to look at the patterns, starting with Zero-day and continuing as One-day, Two-day (which conveniently becomes Tuesday if Sunday is Zero-day), etc.
Start with simple questions like “So if your week has 5 days, and today is Three-day, what day will it be in 6 days?”
Make sure to ask several with the modulus “If your week has 4 days, and today is Zero-day, what day will it be in 4 days? 8 days? 16 days?”
Once they realize that it always goes back to the same day every time the number is a multiple of the days in the week, kids can have fun answering what sound like ‘hard’ questions: “So your week has 9 days, today is Seven-day, what day will it be in 80 days?” (answer – Six-day, one before the same day since 80 is one before an even multiple of 9)
Other interesting questions might be ‘can we have a half-week?’ Or for more advanced students, suppose you have weeks and grods, weeks are 8 days and grods are 4 days. Is it always the same weekday on the same grod-day? What if weeks are 7 days?
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Back when my kids were smaller, I collected clever (ok, I thought they were clever) teaching techniques and published them to a website…a drupal6 website. Since I don’t want to maintain drupal, I’ve moved the bits I’m really attached to here…
We have taken care of a lot of different creatures the last few years, and I thought I’d post a quick summary of what we’ve found as to the difficulty of keeping them happy (the fully detailed methods of care aren’t here, will post later what we used if I have time)
Easiest
sowbugs – only feed about 1/week, carrot/potato, few drops water; keep in ziploc container with thick dirt/leaf layer and small holes, our colonies have been breeding for several years now. 5 yr old can care for independently.
walking sticks – feed daily romaine lettuce or rose leaves. If you forget a day or two they generally are fine, they just stay still to conserve energy. Each lives about 1 year, lays eggs and dies. Use sand or mossy-dirt substrate to let them lay eggs
betta fish – feed few betta pellets daily, clean tank weekly, ours have so far all been doing well for about a year. 6 year old capable of caring for with some help. Nice to have a few tanks near each other so they can have company without fighting.
tadpoles – raise and release – we had about 50/50 survival rate of ones that we rescued from small disappearing pools in the santa cruz river. Feed tiny fragment of algae pellet daily, keep aged water handy and make partial water change every couple days.
dogs – the puppies of course are much more work to train, but dogs are pretty robust pets that will let you know what they need! Also caring for a lost dog and then finding it a home, or fostering an older dog, is not too hard if it is well behaved.
chicks (chicken/turkey) – get them at about 1 week age, younger ones are fragile. Keep in large container with heat lamp, water, food, space to get close or far from lamp. After several weeks can go outside into secure chicken-wired coop with roof. Shade, daily water & food – and you get eggs!
ducks – more cleaning needs than chicks, need swimming pool and more space, but otherwise so far are similar in care.
injured wild birds – once stabilized, can be cared for with daily food and water, every few days cage cleaning, release when able to fly
hermit crabs – seem easy, but when they molt they have some mortality – if kept together may attack the one that has just molted, and sometimes cannot seem to get into new shell. Also they cannot breed in captivity I understand, and they seem to have great desire to get away any time we take them out. If we get more will keep only temporarily and then release at the ocean near Rocky Point.
rabbits – for us, rabbits have been a higher maintenance pet and we had to give back our foster bunny. They need time out of the cage but can be hard to housebreak/keep housebroken. Very sweet, can learn to come when called with treats, but need a lot of time and care. With cooled outdoor area might be easier, but they cannot survive Tucson summers without cooling.
Hardest
I’ve been wanting to start this site for years, finally doing it. Its not themed yet, but a bit of content is there: bTeaching.com – everyday ideas for learning and teaching. The idea is to capture teaching ideas, large and small, and relate them to subjects, age groups, philosophies, etc. Its not as formal as lessonplanet, the ideas can be informal descriptions of games you can play in the car as well as more detailed teacher-style plans. Its intended as a resource for parents, teachers and older kids, but not as a fully fledged curriculum source.
Check it out, and feel free to add ideas!