Here you will see students as young as 4 and 5 years old doing algebra and "advanced" math, without ever knowing it's supposed to be hard.
You are invited to learn how to use this method...



Showing posts with label Math. Show all posts
Showing posts with label Math. Show all posts

Monday, May 7, 2012

Quick Lesson Inverse Functions

You need more than one example but this is a quick 3 and a half minute lesson on how to find the inverse of a function.



In this case what is the inverse of

y = -4x² + 2 ?

Due to my math experience I looked at the multiple choice answers and knew which one it had to be...however due to my carelessness when I tried to show him why I got the wrong answer because I left off a negative when I copied down the problem. We did the problem more than once and this vid shows the last time we did it.

Two principals here:

One: NEVER TRUST THE TEACHER.

Two: You aren't wrong you are just getting more information.

Too many parents (and some teachers) are afraid to work with their kids because they might get it wrong and be embarrassed or what have you. Just get to work and see if you can get the answers...sometimes it's good to get the answer first and then look at the problem. I have had more than one student say it's easy when you know the answer. That's true and then with the thought this is easy you can see how to solve the problem and you know where you are going.

Another thing with some multiple choice tests: you can see answers that reflect common mistakes or misunderstandings of concepts that would lead you to pick the wrong answer. Talk about them. Talk about why they would put that answer as a choice on the test. This often helps deepen understanding.

Now in order to learn how to do these it requires more than on 3 and a half minute video. They can get the rule "just switch the variables and solve" but they will forget the rule in just a few weeks...

You need at leaste three examples of which this would be one of the last ones. They should have also spent some time understanding the basic concepts of Hero Zero and No Fun Get Back To One. (HZ & NFGBT1)

Here is the first example I showed this particular student:

y = x² therefore the inverse would be y = ± √x

First we "swap" the variables: x = y² which is the same as y² = x and solve (NFGBT1) by "square rooting" both sides: y = ± √x

Then you just make them slightly more complex: y = x² + 1 etc...

Then you get two thumbs up because they "get it."



"Example isn't another way to teach, it is the only way to teach." ~AE






More at the house of math.

Saturday, December 3, 2011

Big Blocks Big Fun Big Concepts.


Lately there seems to be a bit of a resurgence in understanding that those big wooden blocks had more purpose than meets the eye.



There are also articles appearing on blogs like this one and others. People seem to be rediscovering a very simple idea. Early is better when it comes to language, and math is a language. Further, the more senses you use the more learning takes place and the easier it is to understand. The brain likes multiple inputs.

Here is a simple wall made with the big blocks, also a lesson on proportion,  wholes, halves and quarters as well as addition and multiplication...just by asking simple questions. What if all the blocks were little ones...well them the bottom blocks would take four...in fact each row would be four...and we can sing a little song about fours as we figure out how many fours it would take if the wall was made of the small blocks, what if we used the halves? Then we'd be counting by twos...  For more advanced students (and teachers) we could do a quick lesson on bases...the most important part is to PLAY.  These kinds of lessons have to be quick and easy and as natural as possible so the kids learn without knowing they are learning...we're just playing using our imagination and asking silly questions as we build stuff.  It's not a formal lesson per se.
Here for sure we are playing. It's a fun preschool math activity AND they learn things that are not so obvious to the casual observer...as Doug Clements explains above.
We talked about the words symmetry, symmetric, symmetrical...
Bust mostly we had fun building a castle.
Then of course there was a little formal math where we practiced all 45 addends...this is a math activity that will be repeated MANY times before the recall is instant and mastery is achieved. Some of the slower teachers will drill these addends over and over again on a daily basis until the students have them down and have acquired a distaste for math in the process. The more enlightened teachers will make this one of a myriad of math activities that keep preschoolers, kindergartners, and first graders engaged for hours over many days and weeks.  Kids never get tired of playing.



Here is another fast easy lesson on finding the area of a rectangle where the students tell you the formula not the other way around. They will forget this in a few weeks, and you can teach it again as a fresh lesson. Seriously. After a a few times they will remember it...internalize it, understand it and not because they looked at these symbols and memorized a formula:

1/2bh = A

The lesson with the blocks above is SO much more powerful than even this lesson:



However, I posted that video several places and the comments about it were how powerful and easy a drawing can be to illustrate the simple concept. I find that presentation creates HUGE "AH-HA" moments in students and teachers alike. Picture worth a thousand words as they say. Kinesthetic experience with blocks worth exponentially more than that...

Learn to use your base ten blocks.

Find us on FaceBook or just go to Crewton Ramone's House Of Math.

Saturday, December 19, 2009

How maths makes the world go round

Always amuses me that people that speak the same language can speak it with subtle differences...like putting an "s" at the end of math and thinking me odd for calling it "the mathematics" instead of just mathematics...anyhow took this from a blog note there is the link to the place I got it, I don't claim to have written it but I do claim fair use. You can take anything off my website or this blog as long as you provide a live link back to the source...




How maths makes the world go round



http://refreshingnews9.blogspot.com/2009/10/how-maths-makes-world-go-round.html


Whether you’re searching for oil, the lost chord or a better kind of carrot, mathematics is the key, says Ian Stewart

Maths makes it: genetic breeding yields a better class of carrot

Like many amateur guitarists, I’d always wondered how to play the opening chord of A Hard Day’s Night. Over the years, I spent hours trying to reconstruct it, but there was something very odd about it: no matter how hard I tried, I could never get it quite right.

In the end, the key to the mystery turned out not to be music, but mathematics. Five years ago fellow Beatles fan and mathematician Jason Brown of Dalhousie University analysed the chord using a method called Fourier analysis, which splits sounds into their basic components. It turns out that the Beatles used a piano as well as their guitars.

It’s not just music that has benefited from a little mathematical knowhow recently. On the sports pages, there has been a bit of fuss about a new type of football, which actually travels in the direction intended. What the reports don’t say is that the design is based on a field of maths called computational fluid dynamics, which uses complicated equations to work out how the air flows past the ball, equations which take into account not just the pattern of the panels, but even details of the seams.

That’s the strange thing about maths. Save for the odd occasion when you want to split the bill at a restaurant, it seems infinitely removed from everyday life. So it comes as a surprise to discover just how much maths is lurking in everyday objects – such as footballs.

We know that maths and technology go hand in hand: the inner workings of Google’s search engine, for example, rely on several areas of advanced maths, such as network theory, matrix algebra and probability theory. The researchers there are highly incentivised to make their work as accurate as possible: improve the maths behind the equations, and oodles more cash floods in from more effective advertising.

But let’s think about something more down to earth: a supermarket vegetable aisle, for example, and in particular, the carrots. The carrot is the second most popular vegetable in the world, after the potato. There are hundreds of varieties, differing in colour, taste, resistance to disease, and ability to survive for weeks in a lorry while being lugged across half of Europe.

All of these types of carrot have been specially bred. One method is to cross-breed different varieties and see what you get; a more modern innovation is genetic engineering. Both rely heavily on maths: it’s used in the statistical calculations required to decide which breed is best, and in the design of the trials that provide the necessary information.

Now, I’d be the first to admit that when you are buying carrots, you don’t need to do that sort of maths. But someone has to, otherwise there wouldn’t be any carrots for us to buy. Old-fashioned breeds don’t work when you have to sell millions of carrots every day. No maths, no veggies.

Anyway, once you’ve lugged that bag of carrots over to the car and dumped it in the boot, you notice that you’re nearly out of petrol. No problem: the supermarket sells that, too. You don’t need to know any maths to stick the nozzle in your car – but without a lot of very difficult maths indeed, there wouldn’t be any petrol in the pump.

Early in September, British Petroleum announced the discovery of a massive new oilfield in the Gulf of Mexico, but you don’t find oil seven miles down by drilling wells at random: you have to know where to look.

Given an accurate map of the rock under the ground, geologists can recognise places where oil may be trapped. But how do you make that map? You make loud bangs at the surface and listen to the returning echoes. By doing the right maths, you can then work out where the different layers of rock are.

It’s a complicated problem, because the echoes from all the different layers of rock interfere with each other. It’s a bit like trying to work out the street plan of a city by shouting loudly and listening to the sounds that bounce off the walls. It has taken decades of work by specialist mathematicians to come up with methods that are practical and accurate: one big oil company now does a quarter of a million of these complex calculations every day.

For centuries, maths has been the main driver of science and technology, and the results have transformed our world. My wife and I have a new grandson, and a few months ago we were able to watch a DVD of him before he was born, made using an ultrasound scan. This employs sound that is so high-pitched that the human ear can’t perceive it. And it works much like oil exploration: the equipment listens to the echoes, and uses maths to reconstruct the shape that must have produced them.

Modern medicine uses many different scanners – CT scans, PET scans, ultrasound. Their common feature is that they use maths to calculate the shape of whatever is being scanned, by analysing the signals that the equipment is designed to detect. The mathematical basis of CT scans was worked out more than a century ago by Johann Radon, a pure mathematician who had no idea that his work – suitably tweaked – would routinely save lives long after he was dead.

Today, medical researchers are developing mathematical ways to detect cancer more accurately. Under a microscope, cancer cells look different from healthy cells, but it takes a trained eye to tell the difference. The mathematics of fractals – very complex geometric shapes – is just what the doctor ordered, helping to capture the difference between the shape of a healthy cell and a cancerous one.

As if that wasn’t enough, maths plays a big part in keeping the environment healthy, too. An example is climate change. Even to detect it, you have to compare what is actually happening with what would have happened if the planet had been left to its own devices. But we can’t rerun the planet’s history, so we have to deduce what would have happened without human intervention. One way we can do that is to model the climate mathematically.

So yes, our fancy electronic gadgets – mobile phones, DVD players, digital cameras, the internet, satnav – rely on a lot of maths. And yes, we use it to make sure that aircraft stay up, Formula 1 cars drive very fast, and gigantic towers don’t collapse. But we seldom realise the extent to which maths has invaded every corner of our lives. It shows up in politics, in opinion polls and focus groups. It controls traffic lights, gets crowds safely into and out of sports stadiums, designs the lenses in our spectacles.

And the reason we don’t notice it is that, entirely sensibly, the maths is kept behind the scenes. If I’m buying carrots, I don’t want to have to learn about the mathematics of genetic trials. If I’m putting petrol in my car, I don’t need to know how to solve the inverse problem for seismic waves. But if I want to understand how my world works, I do need to appreciate that the maths is there. Otherwise, I’ll think that the subject is useless. And if too many of us do that, soon there won’t be enough mathematicians to keep everything working.


Professor Stewart's Hoard of Mathematical Treasures. Published by Profile (RRP £11.99) is available from Telegraph Books at £10.99 + £1.25 p&p. Call 0844 871 1515 or visit books.telegraph.co.uk. He will be speaking at the Royal Society on November 5 at 6.30pm.

Monday, July 20, 2009

Sort Coins





Today we did some simple sorting and counting with a bag of change. The wee ones learned the names of the coins using a three period lesson, although they will need more reinforcement, for the next few hours they have the names of the coins down. Again, it's not about storage, it's about retrieval and building the pathways to the information that is contained in the mind. It has taken us a long time to figure out the mind is not contained in the head, although the brain is. The brain is simply our interface with the mind.

The oldest one still occasionally confuses nickles and quarters...stacking them requires fine motor skills...and gives us a chance to count by fours...we glossed over the equivalency of the coins, that wasn't the focus of the lesson. All we were doing was counting and sorting. Later we will listen to multiplication rock songs...and sing about fours and fives...

In the picture we have sorted out the quarters and are stacking them, later he will be able to ask questions like why do we stack them in fours but dines in fives and pennies in fives and even nickles in fives?

There are a ton of things you can do to play with math concepts everyday...

They watched PBS kids and sorted coins...the youngest one said "this is taking too long" and later "we will be counting coins forever" but he watched TV and sorted coins, sorted coins and watched TV and soon they were in their respective piles...we celebrated with some yays and clapping.