# Featured

## 12 Days of Christmas (1/4/10 - 1/7/10)

The song, the 12 Days of Christmas, is a fun (albeit repetitive) song about the gifts given to "My True Love" on the 12 days of Christmas between the birth of Jesus Christ and the Epiphany, January 6th, the day Christians celebrate the arrival of the Magi (Wise Men). The Mathletes had fun singing this tune, but where is the math?

## Tallest Building in the World (1/4/10 - 1/7/10)

The Burj Khalifa, located in Dubai in the United Arab Emirates, is the tallest building in the world as of January 4, 2010. It was known as the Burj Dubai (arabic for Dubai Tower), until it almost went bankrupt and was bailed out by the leader of neighboring Abu Dhabi, Khalifa. The statistics are:

Height: 2,717 feet (828 meters)

Floors: 160

Elevators: 54

## Oragami Cubes to make buildings (12/22)

The Mathletes made six parallelograms out of square colored paper and then connected them using perpendicular lines to make a cube. During the holiday break, Mathletes should make as many of these cubes as possible and then put them together to make a building .

See directions on the attached YouTube link http://www.videojug.com/webvideo/how-to-fold-an-origami-cube-with-six-pieces.

Happy Holidays.

## Multiplication (12/15 thru 12/21)

We explored multiplication tables with grades 2-5 beyond the standard 10x10 table. These included powers of two, unit fractions, prime numbers, even numbers, and standard tables up to 30x30. Mathletes should work at their own pace with as many of the tables with which they are comfortable. The answers are provided after each blank table. Do not print out the entire file as it is 19 pages.

## Doubling, Powers of Two, and Binary Numbers (12-8 thru 12-14)

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This week we practiced doubling numbers from 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, and so on. The children were able to recite the first ten numbers in this sequence in less than 10 seconds. They should practice that sequence this week; and the ambitious Mathletes should try to double 30 times (see the attached worksheet).