Educator How-To: Why square it when you could cubit?

Published by Kat on March 23, 2013 at 11:00 am in Education

The cubit was Ancient Egypt’s standard unit of measure, much like our foot or meter measurement. There were two cubit lengths in ancient Egypt: the short cubit and the royal cubit. The short cubit was the distance from the elbow to the tip of the middle finger of the pharaoh. The royal cubit was the distance from the elbow to the middle fingertip, plus a palm width.

The ancient Egyptians also had smaller units of measure called the palm and the digit. The palm was the width of your four fingers held close together, and the digit is the width of your index finger. So, to review:

•   A cubit is the length from your elbow to the tips of your fingers
•   A palm is the width of your four long fingers
•   A digit is the width of your finger

We’ve put together a handy little activity to teach your kids about ancient Egyptian units of measurement below:

Materials
Measuring tape
Paper
Pencil
Markers
Scissors
Stiff cardboard

Procedure
1.   Separate children into pairs. They will take turns measuring each other from elbow to the tip of the middle finger using the measuring tape. They should record this number, as they will need it shortly.
2.   Now, using stiff cardboard, students will measure out the same length as their measurement from elbow to fingertip and cut the cardboard to this length in the shape of a standard ruler.
3.   They should then divide the cubit into palms and digits using four fingers of the hand for the palm and one finger-width for the digit divisions.
4.   Using markers, students should neatly record the following information on their cubit: Their name, length of the cubit in inches, and length of the cubit in centimeters.
5.   Ask the class if all of the cubits will be the same length. Why or why not?
6.   Record all of the cubit lengths from the entire class and average that number. This could be the standard length of the “class cubit.”
7.   Measure different items using your cubit.

Educator How-To: Prep for Pi Day with a circle-folding exercise

Published by Kat on February 22, 2013 at 4:02 pm in Education

Pi Day is all about circles, circumference and diameter. Pi (approximately 3.14) i~~s delicious~~ is the ratio of a circle’s circumference divided by its diameter. This ratio is the same for all circles.

In the spirit of Pi Day, let’s see what we can do with the fabulously fun circle and what we learn along the way by making some simple folds.

You will need the following supplies:

•   Ruler
•   Pencil
•   Paper
•   Compass
•   Markers
•   Scissors
•   Scotch Tape™
•   Small piece of candy

Procedure:

1. Use a compass to draw a 7-inch circle. Carefully cut the circle out.

2. Describe the properties of the circle.

3. Can any other shapes be made using this circle? Let’s find out.

4. First, fold the circle in half and open the circle back up. Each half of this circle is called a semi-circle. Notice that both halves of the circle are identical. We say the halves are symmetrical, or have symmetry.

5. Can you think of anything in the classroom that is a semi-circle? A protractor is a semi-circle. How many degrees are on a protractor? If you don’t know, investigate. There are 180˚ on a protractor, so, how many degrees in a full circle?

6. Now, fold the circle into fourths, then unfold the circle and locate the center. Mark the center using a marker or pencil.

7. Using a ruler, draw a line from one side of the circle to the other, making sure to pass through the center. This line is diameter of the circle.

8. Using a ruler, draw a line from the center of the circle to one point on the edge of the circle to create a radius.

9. Next, fold one side of the circle down so the edge meets the center point. Unfold and use a marker or pencil to darken the line of the fold. This line is called a chord.

10. Re-fold the circle along the chord line and fold an additional edge to the center of the circle to form an ice cream cone-like shape.

11. Fold the remaining edge of the circle to the center to form an equilateral triangle.

12. Make a new shape by folding one vertex of the triangle down so that its tip touches the center of the side opposite to it. What is the resulting shape? The shape is a quadrilateral and a trapezoid.

13. Let’s make another shape: Fold one acute vertex so that it meets one of the obtuse vertices. What is the shape created as a result of this fold? You should come up with the terms: parallelogram, quadrilateral, and rhombus.

14. Unfold the shape until you get back to the larger triangle. Then, fold each of the three vertices to the center point. The new shape that is created is a hexagon.

15. Again, unfold the shape to the original triangle. Fold the triangle so that all of the vertices touch at a single point to form a triangular pyramid. Is this shape a polyhedron?

16. Lastly, fold all of the top halves of the triangles down so they cross each other. Use tape to secure the sides. This creation is a truncated triangular pyramid. It can be used as a space to put a special treat.

Vocabulary

Property – an attribute common to all members of a class

Semi-circle – a half circle, formed by cutting a whole circle along a diameter line. Any diameter of a circle cuts it into two equal semicircles

Symmetry – when one shape is identical to another

Diameter – the length of the line through the center and touching two points on its edge; sometimes the word ‘diameter’ is used to refer to the line itself

Radius – the length of the line from the center to any point on its edge. The plural form is radii. The radius is half the length of the diameter.

Chord – a line segment that only covers the part inside the circle. A chord that passes through the center of the circle is also a diameter of the circle.

Equilateral Triangle – a triangle in which all three sides are congruent (same length)

Vertex – typically means a corner or a point where lines meet; every triangle has three vertices.

Polygon – a number of coplanar line segments, each connected end to end to form a closed shape

Quadrilateral – is any 4-sided polygon

Trapezoid – a quadrilateral which has at least one pair of parallel sides

Acute – an angle less than 90°, or to a shape involving angles less than 90°

Obtuse – an angle greater than 90° or a shape involving angles of more than 90°

Parallelogram – a quadrilateral with both pairs of opposite sides parallel

Rhombus – a quadrilateral with all four sides equal in length

Hexagon – a polygon with 6 sides

Triangular Pyramid – a pyramid having a triangular base; the tetrahedron is a triangular pyramid having congruent equilateral triangles for each of its faces

Polyhedron – a solid figure with many plane faces, typically more than six
Truncated Triangular Pyramid – is the result of cutting a pyramid by a plane parallel to the base and separating the part containing the apex

For more Pi Day fun, join us at the Museum from 10 a.m. to 1 p.m. on Thursday, March 14 for an event celebrating all things Pi! Expect crafts, Einstein-themed goodies and pies of every variety from Pi Pizza Truck and Oh My Pocket Pies. Click here for more info!

Educator How-To: Make your own Fabergé — ahem, Faux-bergé — egg, complete with a tiny surprise!

Published by Kat on January 25, 2013 at 4:09 pm in Fabergé: A Brilliant Vision

Hearing the name “Fabergé” evokes the splendor and extravagance of Imperial Russia. The famous House of Fabergé designed renowned Imperial Easter Eggs for the Romanov family, as well as an array of other practical items for the wealthy patrons of Europe.

Visitors to HMNS can glimpse this grandeur beginning Feb. 1 in a special exhibition from the McFerrin Collection. The exhibit, available with general admission, expands upon the collection exhibited in 2010 and features more than 350 objects, including a newly acquired Kelch egg and a frame that once belonged to Elizabeth Taylor.

Make your own Faux-bergé eggs with this simple hands-on activity! Decorate your hinged little works of art and design a special surprise to go inside:

Materials:
•   Plastic egg – any size
•   Quick-dry craft glue
•   Old paint brush – to apply glue
•   Glitter in the color/s of your choosing
•    Thick cardboard
•   Scissors
•   Something fun to put inside your egg
•   Fake gems or other sparkles to decorate your creation

Procedure:
1.   Cut a circle of cardboard to fit in the bottom half of the egg as a resting spot for your object. (In our case, a very beautiful Glittersaurus rex.)
2.   Apply glitter to one side of the circle and set aside.
3.   Use a small piece of cardboard to create a hinge for your egg. Glue one side of the hinge to each half of the egg and allow to dry well.
4.   Paint your egg with glue and apply glitter liberally. Dry well.
5.   Apply gems or other decorations. Allow to dry.
6.   Insert your cardboard circle into the bottom of your egg. It should fit snugly.
7.   Lastly, put your treasure inside of your Faux-bergé egg.

Fabergé: A Brilliant Vision is organized by the Houston Museum of Natural Science with the McFerrin Collection.

Support provided by The Wortham Foundation, Inc.

Educator How-To: Calculating your birthday in Maya Long Count

Published by Kat on December 21, 2012 at 11:50 am in Education

Adapted from “Cracking the Maya Code,” a NOVA activity.

We’re familiar with a method of tracking time that uses days, months, years, decades, and centuries. This method of timekeeping is based upon the Gregorian Calendar System. The Maya, however, measured time in kins, uinals, tuns, katuns and baktuns using a system called the Long Count. If you add the numbers in a Maya Long Count date, the sum is the number of days from the beginning of the Maya Fourth Creation: August 13, 3114 B.C.

Maya Long Count dates are written as a series of numbers separated by periods. For example, 12 . 18 . 14 . 11. 16 (December 31, 1987) is the date you will use as a starting point for your calculations. The same date is shown below in its separate component parts above its representative glyph.

Step One: Using the “Maya Long Count Conversion” chart above, convert each place value in the date 12 . 18 . 14 . 11 . 16 into days. Add these five numbers together and subtract 2 to get the total number of days. A formula has been provided below to help you get started. You will need to do your calculations on another sheet of paper.

12*Baktun + 18*Katun + 14* Tun + 11*Uinal + 16*Kin – 2 = ________days

Step Two: Record your birth date (in the Gregorian method). If you were born prior to January 1, 1988, calculate the number of days from the day you were born to December 31, 1987 (Answer A). If you were born on or after January 1, 1988, calculate the number of days from this date to the day you were born (Answer B). Keep in mind that leap years have an extra day. The chart below will help you with the number of days for each month. Record this number.

Note: The following are leap years and have a total of 366 days (a 29th day in February): 1960, 1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008, and 2012. All non-leap years have 365 days.

Step Three: If you calculated answer A, subtract this number from the Step One answer. If you calculated answer B, add this number to the answer from Step One. Record this number..

Step Four:
Convert the number of days since the Maya Fourth Creation to your birth date in Maya Long Count using the “Maya Long Count Conversions” chart.

To calculate your birthday:

How many whole baktuns are there in C days? This number (we’ll call it D) goes in the baktun position.
How many days are left over from C after you subtract the number of days in D baktuns? Call this E.
How many whole katuns are in E days? Call this number F and put it in the katun position.
How many days are left over from E after you subtract the number of days in F katuns? Call this number G.
How many whole tuns are in G days? Call this number H and put it in the tun position.
How many days are left over from G after you subtract the number of days in H tuns? Call this number I.
How many whole uinals are in I days? Call this number J and put it in the uinal position.
How many days are left over after you subtract the number of days in J uinals? This is the number of kin in your birthday.

Fill in the spaces using your calculations, and check your answer here by plugging it into the applet.