Welcome to Dave’s Digital Magic #2
Here are 5 links for you to explore.
1. THE FEATURE OF THE WEEK!
Nothing new here, but when I found this, it reminded me of some of the really interactive things I’ve done in my classroom, but didn’t use as much as I should.
– – –
2. LEARNING AND ENGAGING ONLINE
Teachers can get a FREE ACCOUNT! There are soooo many classroom possibilities.
3. GLOBAL AWARENESS
4. MATH CENTRAL
5. THINGS THAT MAKE YOU GO HMMMMMM…
A Feature in the The New York Times, By Po Bronson. I will let the article speak for itself:
Later, when given a much more difficult test, these results were magnified. It really is worth reading the whole article, but here is a key point about the research above:
More food for thought from the article:
In a nutshell, praise effort rather than intelligence. The article goes on to mention the value this has on developing persistence when faced with failure, while praising intelligence increases the stress and reduces the desire to face such challenges. I will be thinking about this a lot over the next few days both at school with my students and at home with my own kids. – – – – – Po Bronson’s blog, “How Not to Talk to Your Kids” Part 2, Part 3, Part 4. From Part 4:
“A common praise technique that people use (I know I did it with my tutoring kids… up til a few weeks ago, that is….) is to use a present success to control future performance. For example, if a typically-sloppy child writes an essay that’s atypically legible, a parent or teacher may say, “That’s very neat: you should write all of your papers like this.” Even if it’s meant as sincere praise and encouragement, the research shows that’s not only an ineffective way to praise. In fact, like praising for intelligence – it can actually damage a child’s performance. Here’s what is going on…”
– – – –
Have a great week!
‘The Rules’ and ‘The Reasons’,
‘The How’ and ‘The Why’
for Multiplying Integers.
I uploaded a couple pages of my Math Model Book for a ‘Pair-a-Dimes’ post, “Assessment & Rote Learning: Math Conundrums“… and thought I would share these very practical resources here.
The first page has The Rules for Multiplying and Dividing Integers.
Next, using counters, I look at Why the Rules for Multiplying Integers Work*. I call this lesson “Why is a negative times a negative a positive?” and slowly build up to this at the end of the lesson. I enjoy seeing the a-hah moments in students when they finally understand this concept.
*It is very important to have pre-taught the concept of zero before this lesson, (the same negative and positive number together cancel each other out: together -4 and +4 = 0).
But what about division you might ask? I find this harder to show with counters so I usually explain that every multiplication question has two equivalent, related division questions:
If 3 x 4 = 12 Then 12 ÷ 4 = 3 and 12 ÷ 3 = 4
So if, -3 x -4 = +12 Then +12 ÷ – 4 = -3 and +12 ÷ -3 = -4
This makes further sense to students when they realize that multiplying two integers with opposite signs = negative, and they can see that the same rings true for division as well.
It doesn’t get much easier than this:
A round table has four deep pockets equally spaced around its perimeter. There is a cup in each pocket oriented either up or down, but you cannot see which. The goal of the game is to get all the cups ‘up’ or all the cups ‘down’. You do this by reaching into any two pockets, feeling the orientation of the glasses, and then doing something with them, (you can flip one, two, or none). However, as soon as you take your hands out of the pockets the table spins in such a way that you can’t keep track of where the pockets you have visited are. If the four glasses ever get oriented all up or all down a bell rings to signal you are done. Can you guarantee that you will get the bell to ring in a (maximum) finite number of moves, and if so, how many?
– – – – –
Please feel free to post questions or your best answer in a comment… but do not ruin the challenge for others by explaining how you got to that answer here! If you feel compelled to share your method, please do so by contacting me. Thanks!
You have two glass orbs of equal strength and a 40 story building.
Your task is to determine the highest floor from which you can drop an orb without it breaking.
What is the least number of drops required to do this?
Both orbs may be broken in order to determine your answer.
– – – – –
Please feel free to post your questions or best answer in a comment… but do not ruin the challenge for others by explaining how you got to that answer here! If you feel compelled to share your method, please do so by contacting me. Thanks!
Image: ‘Sphere_2720’by doviende
With the tag, all project photos can be seen in a single space.
A description of the project by Cool Cat Teacher is here.
The Trig. assignment/Ruberic developed by Darren Kuropatwa is here.
What a great assignment to do for Fractions or Geometry!
The use of Hotspots is what really ties the photo to the learning!
(‘Add Note’ on a Flickr photo).
This is “Tenny’s trig” photo from Darren’s class. (With Hotspots Here)
This can be used in Art and quite frankly, across the curriculum, but I really like the potential for using it in Math. Congrats to Darren – this is brilliant!