## Sunday, March 9, 2014

### Year 2 - Lesson 14

The kids were playing around a lot and not listening this class. They were climbing under the table, swinging on their chairs, rolling around, poking each other… Well it’s a good teaching experience for me, I guess J
1.      Which of the operations below makes the largest odd number?
a)     3*1+2*4
b)     3*(1+2*4)
c)      3* (1+2)*4
d)     (3*1+2)*4
2.     Kristina, Max, Dima, and Matthew had an apple eating contest. The person who ate the most apples won. Kristina ate more apples than Max, and Dima ate fewer apples than Matthew. We also know that Dan did not win the contest. Who ate the most apples?
*Do a problem about backwards problem solving with shapes and adding/subtracting to get to a result*

In 36 years, I will be 100 years old. How old am I now?

4.     Othello symmetry
5.       Order R, A, and C from least to greatest. What do they spell out?
7-2 = R
1+3=A
10-8=C
6.       Mugesti 6 km left. Behaiesti 4 km left. Cripesti 2 km right. Mormaiesti 5 km right. What’s the distance between Behaiesti and Mormaiesti?
7.       Vivi said to Bibi, who is standing behind him, “Behind me, 4 coworkers are standing”. Bibi answered “In front of me, only 3 coworkers are standing”. How many clowns are in the line?
8.       Dan has a bag of yellow, orange, red, green and brown candies. There are 20 pieces of candy. He first eats only the yellow, red and orange ones. How many pieces are left in the bag?
9.       Dan left his home at 8:00 AM. He left school at 12:30 PM. The walk home takes 30 minutes. How long was he gone from his house?
10.   What number is next? 209, 902, 290…?

Play mastermind and many-people blokus – we didn’t get to this

### Year 2 - Lesson 13

Kangaroo problems edited from 2011 and 2010 – we’re getting ready for the Math Kangaroo
1.      Fourteen children lined up in pairs. How many pairs were there?
The don’t really know how to divide numbers yet, so they drew 14 dots, circled two at a time and then counted how many circles they have.
2.     Today it is March 18, 2010, and I am 7 years old. How old will I be on March 18, 2020?
The kids counted how many years is it from 2010 to 2020 and then added that number to 7.
3.     There were 9 four-person tables in the room where Max had his birthday party. When Max and all his guests sat down, there were still 7 empty seats. How many guests came to Max’s party?
One of the kids organized everyone to draw tables and count seats. J Then he told them to subtract 7 from that number. Wow, good management skills :)
4.     Sasha had \$20. He bought one carton of milk, 10 bananas, one loaf of bread and two packages of butter. With the money he had left over, he bought lollipops. How many lollipops did he buy?
a)     Milk: \$2,
b)     Lollipop: \$1.50,
d)     Butter: \$2.50,
e)     10 Bananas: \$5
This is a relatively simple counting problem – I presented it like a working-backwards puzzle to the kids so that they get more familiar with working backwards in problems.
5.     Matthew has 3 pieces of candy, Katya has 2 pieces of candy less than Dima, and Dima has 4 times as many pieces of candy as Matthew. How many pieces of candy do Matthew, Katya, and Dima have altogether?
This one was pretty easy they figured it out after a few moments of calculating and scribbling.
6.     Today is 3/12/2011. No item can be sold after the date shown next to it. Which of the items cannot be sold?
a)     Cheese: 9/15/2011
b)     Juice: 3/4/2012
c)      Butter: 7/11/2011
d)     Yogurt: 2/25/2011
It can never hurt to know how the calendar works.
7.      In 36 years, I will be 100 years old. How old am I now?
Another backwards problem solving problem. When they solved they were like “Oh really you’re 64? Oh we thought you were younger…” Haha for a few moments they actually believed it
8.     Katya has several dogs and 4 cats. The number of her cats’ ears is equal to the number of her dogs’ paws. How many dogs does Katya have?
The thought about how many ears each cat has, then added it together for all the cats, and then split that amount to be four legs of the dogs.
9.     Mr. and Mrs. Kangaroo have three daughters. The youngest is 5 years old. The middle daughter is 4 years younger than the oldest daughter and 6 years older than the youngest daughter. How old is the Kangaroos’ oldest daughter?
Another problem where to solve the problem you first have to read the whole problem and only then you can solve it. This is good practice.
10.  Play “I’m thinking of a domino that…” by giving hints about the domino and having the kids rule out all the other dominoes until they get to that one. If there is still time left, play Chocolate Fix.
This was a nice cool-down game but the kids were all really tired by then (remember, they’re coming after school and it’s spring now and their stored energy from sitting in school all day long for a year is starting to escape J)
Only a couple kids stayed to do Chocolate Fix – the others ran off to play. This is actually a very good mental rotation game and also it involves thinking in a venn-diagram-y type of way – the different clues have to overlap in your mind to solve the puzzle.

### Year 2 - Lesson 10

·         Color a sheet of paper symmetrically, then fold it symmetrically, and then cut it out in different ways and see if the symmetry is still there
·         Nim
·         Inverse Nim
·         Flip a triangle made out of poker chips (4-3-2-1 rows) upside down by moving only three poker chips
·         Color a (4-3-2-1 rows) triangle made out of circles with three different colors so that no two matching colors touch.
·         Play ThinkFun’s Trap the Hare game
·         Play Othello
·         20 questions

·         Play bingo with addition and subtraction (14 could be 11+3, 3 would be 4-1, etc.). If kids are younger, using smaller numbers (only up to 10) will work better.
 12 15 7 3 8 9 1 11 13 6 2 4 10 0 5 14

 9 8 2 3 6 0 15 5 10 14 13 11 4 7 1 12

 13 14 6 1 0 5 4 7 2 12 9 8 3 11 15 1

### Year 2 - Lesson 11

Some ideas are borrowed from информатика школа 2100
·         A man walked into a hotel and went on the elevator to the third floor. Then he went up again the same amount as last time. What floor is he on now?
At first they said the 6th floor (and that’s what I expected), and then after drawing diagrams, they counted and saw that it was actually the 5th.
·         How many squares are needed to make a square double the size?
They had no idea how to do this at first, but after a few hints, the figured it out.
·         Fold cube nets into cubes
For some reason the kids loved this, even though most of their cubes looked more like spheres :D
·         Help K. get some strawberries – one jar says “the strawberries are here” and the other one “there are no strawberries in either of these jars”. We know that either the labels are both correct, or both wrong. Which jar should K. open to get some strawberries?
They tried one option, it didn’t work, tried the other, it worked, and they were done.
·         K, M, and D are playing ball. One of them loses the ball. You know that one of these statements is true and one is false:
1.      K. lost the ball
2.      M. didn’t lose the ball.
Who lost the ball?
Well I think this is a good problem but it didn’t go anywhere because at this point the kids started fooling around so I moved on.
·         Number – Name (letter) codes:
1.      (name of kid)- 1234
2.      (name of kid) - 3454
3.      (name of kid) - 6454
4.      (name of kid) - 3476
a)      1 – letter
b)      2 – letter
c)      3 – letter
d)     4 – letter
e)      5 – letter
f)       6 – letter
g)      7 – letter
Let them then decode 14, 7454, 1267, and 34674
Figure out which number is whose name.
Now make your own number codes.
Have a partner figure them out.
This was a fun and relatively simple activity.

Make a drawing:

1 – triangle
2 – square
3 – circle
4 – green
5 – blue
6 – red
7 – choose your color

A.   Draw a big 3
B.   Inside the 3, on the left draw a 1
C.   Inside the 3, on the right draw a 2 so that it intersects with the 1
D.  Draw a little 1 somewhere in 3 but not in the other shapes
E.   The part that is both 2 and 1 color 6
F.    Color the rest of 1 with 4
G.   Color the rest of 2 with 5
H.  Color the rest of the 3 with 7

Some of the kids did this, others ran off to play because they were tired.