The Week in Review, 3/12 - 3/16

Last week we took an early Spring Break in order to get some big, time-sensitive projects done (one of the privileges of homeschooling, no?). While we didn't formally "do" school each day, the big girls did math (we do math almost every day -- even during the summer!), and the little girls got some good Montessori work done. We also threw in a quick science experiment for good measure, and our 5-y.o. -- frustrated by the "mental math" that Singapore Math sometimes requires -- pulled out the bead frame to supplement her math work. 

Some highlights from the week:

G - geometric solids, geometric figure cards...

...and geometric solids matching cards:

G - opposites matching:

G - world map...

...and labels:

G - color box (3?), grading seven shades of a color from lightest to darkest:

E - exploring magnetic and not magnetic (and then she took to threading a nail into the circle end of a safety pin, which kept her busy for a looong time -- who knew? :)

E - sorting three colors of bears

E - nuts and bolts activity:

E - marbles on golf tees:

E - Matryoshka dolls:

E - Melissa & Doug grill set (slicing/tonging/skewering (akin to beading/stringing, only easier because the skewers are hard)):

E - open/close; pushing toothpicks through teeny holes in spice jar lid: 

S - Singapore Math 2B. As I mentioned, Singapore Math puts a great emphasis on "mental math," or doing math in one's head. For example, for 300 - 99, they tell her to think of 300 as 200 + 100. Then, they tell her to subtract 100 - 99, which equals 1. Next, she adds 200 + 1 to get her answer: 300 - 99 = 201.

It's a good system, but S was having difficulty -- for her, it would have been easier to stack all of the problems and work them out by subtracting and borrowing. I didn't want her to have to do all that borrowing, and even Singapore Math didn't want her to do all that borrowing -- after all, the whole point of the exercise was to make subtracting easier!

But because she was getting frustrated, I suggested that she grab the bead frame. She had used it before but needed a quick refresher. Once I reminded her how to use it, she set to work and knocked out all of her textbook and workbook exercises in no time flat! 

For those of you who are unfamiliar with it, may I present the large bead frame (it typically comes in large and small -- we have only the large one). The colored beads are on wires that correspond to the decimal system (units are green, tens are blue, hundreds are red, thousands are green, and so on). S will now demonstrate the process she went through to solve the problem 800 - 98:

First, 800, or 8 hundreds:

She needs to take away 9 tens, but she doesn't have any tens. She "gives one hundred back to the bank," or slides one hundred bead to the left...

 ...and exchanges it for 10 tens... 

...she takes away nine tens and needs to take away 8 units, but she doesn't have any units, so...

...she "gives her ten back to the bank..."

...and exchanges it for 10 units (she's working fast now, can you tell!? My camera could barely keep up :)...

...she takes away 8 units...

...and she's left with her answer: 702

After she got the hang of it, the problems were easy...

...and eventually she was able to do them in her head...and isn't that the whole point? 

(PS - "The bank game" language is a holdover from S's many years playing the bank game with the golden bead materials. For a very basic tutorial on the bank game, click here)

We waited for a sunny day and did experiment #116 from the Janice vanCleave book. We put ice cubes in two zip-loc baggies and closed the tops. We covered one bag with a black piece of paper and the other with a white piece of paper. The girls hypothesized which set of ice cubes would melt faster -- those under the black paper or those under the white. This is what the ice cubes looked like when we started: 

We covered the bags with the paper and checked the ice cubes every five minutes to see which set melted faster:

This isn't the final photo, but you can tell that the ice cubes under the black paper melted faster than the ice cubes under the white paper. We talked about how the sun gives off energy in the form of light; black absorbs light energy better than white, so the temperature under the black paper was higher and the ice cubes melted faster.