Math: Making Calculators and *Really Difficult* Multiplication

22 08 2010

In Mathemagic, we are reading about counting systems, and how computers count in base 2 instead of base 10. So I thought it would be fun to build an adding machine of some description. Evil Mad Scientist Laboratories helped us out with its Fraction-of-an-Inch Adding Machine. Here is Floppy, reading the build instructions:

Cutting out the patterns:

Furiously gluing the pieces:

And working the finished product, which he thought was awfully cool:

From there, we moved on to maddening difficult multiplication problems. Here they are:

I can tell when the math is too hard: First Floppy gets angry and frustrated, throwing his pencils and saying “I can’t do it!” Then we stop. I say, “It’s OK, we don’t have to do this today. Another time.” Then he says, “No, I want to do it!”

Then he asks for food, usually something sugary, like cereal. Did you know your brain consumes fully 75% of your available blood glucose — and more when it’s thinking hard? I did. I can watch the Floppy thinking and tell….


Math: German 1-10 (and the end of our 1-10 series)

10 07 2010

Germany was our last country in our 1-10 math and culture series, and for a change, we visited Germany for a weekend frühstück (breakfast). According to my own memories of cheap B&Ba, as well as the internet (e.g., here), a traditional German breakfast is midway between what USians would call “continental breakfast” and what we would call “picnic lunch.” Cold cuts, sliced cheese, breads, spreads, and soft-boiled eggs, plus maybe some fruit or muesli. Here was our version this morning:

You can’t tell it by his face, but Floppy was super-excited at this breakfast buffet.

We ate our meal listening to this playlist of Austrian/German music, and between the all of it felt quite continental. There are lots of youtube videos that will teach you to count 1-10 in German. We used these two, which were each nerdily charming in their own ways.

Math: BTUs and multiplication

10 07 2010

We tackled a *very difficult* multiplication problem in this math lesson. In this exercise, again from Aunt Betsy’s math textbook, she had us calculate the BTUs needed to cool a room with an air conditioner, using a complicated formula that required you to figure the area of all the room’s windows — separately and added together — the area of the room itself, and the room’s perimeter. Then each of those numbers had to be multiplied by a factor taken from forms that really do calculate these things. One thing I love about Betsy’s text is it uses real life examples that show how math functions are used in the real world. We could have done the calculation for a room in our house, but for once we kept it simple(r) and used the sample room dimensions she provided. It took most of an hour, but Floppy was finally able to complete this incredible problem. Here’s the finished worksheet, followed by a picture that illustrates how challenging this work is.

Math: Polish 1-10.

7 07 2010

We used this video to learn our Polish 1-10, but the meal had me stymied.

It was such a hot day, today. Well up over 90, and we don’t use air conditioning, though our circa 1960 era house was designed to waste as much energy as possible, not catch cross-breezes. Anyway, not exactly the ideal time to be cooking a heavy Polish meal. I could think of some Eastern European-type hot weather dishes — cucumber salads, chilled fruit soup — but either didn’t have the appropriate ingredients or didn’t think they were substantial enough to count as a meal.

I ended up with a not-very-authentic, but very, very delicious, version of this bialy barszcz and an even more approximate Salata po Polsku inspired by this.

The barszcz (said “barsch”) turned out to be so delicious I will write up the recipe for you.

Bialy Barszcz ala DBI Schoolroom

  • 4 parmesan-garlic lamb sausages
  • 4 eggs
  • 1/2 cup no-knead bread sour dough
  • 1/4 cup dill pickle jar liquid (from vinegar-based, not kosher dills)
  • 3/4 cup sour cream
  • 2 Tbsp flour
  • 1/4 cup whole milk or cream
  • 2 cloves garlic, minced
  • salt
  • pepper
  • 1 tsp marjoram
  • 2-3 ounces sharp cheddar cheese, diced
  • 2 large slices no-knead bread, cubed
  • horseradish (we used wasabi powder)

Chop the sausages into bite-sized chunks and put them in about a quart or a bit more of cold water along with the whole eggs (still in their shells). Heat to a rolling bowl, cover, turn off the heat, and let sit for 18 minutes. Fish out the eggs and return the water with sausages to a simmer. Cool the eggs in cold running water, peel and slice them and set them aside. Take the sour dough in your hand and pull off dime-to-nickel sized lumps and toss them in the simmering sausage water to turn into dumplings. Add the pickle-liquid. Leave the soup to simmer while you prepare the bread and cheese cubes, and place a handful of bread cubes, cheese cubes, and a sliced egg in each person’s soup bowl. Mix the sour cream, garlic, and the flour. Working quickly, whisk the sour cream mixture into the soup, whisking rapidly to prevent lumps (don’t worry if there are a few). Stir in the milk,horseradish,  salt & pepper to taste, and the marjoram. Taste and correct seasonings as needed. Pour into the waiting soup bowls with the bread, cheese, and egg slices. Serve with a green salad. Serves 4. Yum.

Math: Multiplication (and Ranting)

19 06 2010

Floppy’s last day of real school was Friday, and he came home with the usual pile of art projects plus a letter from his principal, politely and calmly letting us know that his school is a federally-designated School In Need of Improvement in both math and reading, and that he was required to inform us that school districts are required to offer parents at substandard schools such as our own a choice of a better school. Except the only other elementary school in my town is also a School In Need of Improvement, so we can just fuck right off. The tone of this letter was relaxed to the point of complacency, had a distinct whiff of “the guvment is making us do this, so we have to, but we don’t care,” AND also did not offer any proposed solutions to the problem. Naturally, it got me so angry I can scarcely see straight. Since I can’t afford private school and don’t want to move, we renewed our homeschooling with greater vigor.

Luckily, this isn’t terribly difficult. Floppy had been begging for homeschool all week. Lately, Floppy has been saying “I love math!” to a degree that is positively nerdalicious. He loves learning math more than I do teaching it to him — when I am trying to show him something challenging and above his head, like multiplication, I wear out much faster than he does. I’m saying, “enough” and he’s saying, “Just one more problem? Please?”

Unlike his school, I must be doing something right.

Today we learned the distributive law of multiplication, how to multiply two-digit numbers, and — most important of all — what “double the stakes” means in poker. Here’s the Floppy doing his math thang:

Yes, that is a tail on the table. What?

Math: 1-10 in Russian

5 06 2010

Russian is another language I was looking forward to one-to-tenning with Floppy, because at one time (high school) it was a language that I (sort of) knew. So instead of hunting up one Internet and down the other youtube, I just taught him myself. Also, we made a Russian dinner. We had tea in glasses with a spoonful of blackberry jam in the bottom, pirogue s kapoustoy (a sort of cabbage pie),  and a blackberry compote. The tea and compote especially took me right back; if I had sliced up a cucumber with some dill to go with all this it would have been right out of my memories of obyet in Minsk.

Here’s the dinner. I wish I had brought out my Russian table linens to serve all this. Shame I didn’t!

Here’s the compote I made, which is a delicious vegetarian alternative to fruity jello, and which I adapted freely from this recipe:

Russian-style Blackberry Compote

1 12 oz. package frozen blackberries

1 cup water

1/2 cup sugar

3 tbsp cornstarch

1/4 tsp salt

1/2 tsp balsamic vinegar

Mix the dry ingredients together. In a saucepan simmer the water with a small handful of the frozen berries for about 3 minutes. Then drain the cooked berries, reserving the liquid and returning it to the saucepan. Put the cooked berries in with the rest of the still-frozen berries in a smallish bowl. Whisk the dry ingredients into the berry water in the saucepan and stir until smooth. Heat to boiling, stirring constantly, and boil and stir until the mixture becomes very thick (a minute or two). Then stir into the bowl of berries along with the vinegar. Chill until cold. Yum.

After dinner, we read from Mama’s 1990 Russian/Byelorussian trip journal. Floppy thought it was boring, and poorly written besides, and a lot of it was totally embarrassing in that return-to-your-youth way, but I was surprised to see how much of it I had actually written in Russian. And the parts that were in Russian, I often could no longer understand! A nice trip down memory lane, as well as a counting lesson.

Math: Multiplication

16 05 2010

Multiplication is really a little above Floppy’s head still, so I was amazed at how well he was able to do today with the basic concepts. We started by considering how many 3 dozen doughnuts might be. We learned the words “factor” and “product,” and all the different ways you can symbolize multiplication. He was quick to understand the function of one as an identity element in multiplication, and was able to answer which number functions similarly in addition? (0.) He also readily remembered and applied the commutative law to multiplication. More difficult was multiplying three numbers, but with some help he was eventually able to show that 3 · 4 · 5 = 60.

Here he is, hard at work with the lilacs: