Wednesday, November 28, 2012

Today we did an activity sheet in group-projects called "Circumference versus Diameter." It was about circumference, radius, and diameter formulas. We measured some of the stuff Mrs. Roxanne brought over including some lids, containers, and even an easy-button using a yard/metric-stick. We measured the items by centimeters. We determined the radius, the circumference, and the distance of each of the objects. We also went over formulas including how the circumference, radius, and diameter are related. We recorded the data on a table and then we answered the questions using the formulas.

We did another activity called "Right or Not?" It was a group activity and we used a bunch of square-tiles to determine the areas of angles. We use three different-shaped square tiles to form a triangle. We would then determine if the triangle was obtuse, right, or an acute angle.We then filled in another table. We add the area of the smallest square and third squares to find the areas of the two smaller squares. We then make up the numbers for the areas of the smallest squares and the areas of the third squares. In the next page we have to determine the angles based on the descriptions of the length of the sides. I thought it was very interesting how three squared tiles of different lengths can form different sized-triangles.

Here is a website that further explains the formulas of a circle:

This is a video about the formulas for circles:


Final Blog






This is my last entry for this semester. We were given study-guides for the test. I have to admit that I’m pretty scared. This test requires us to memorize a bunch of formulas. I could easily get some of the formulas mixed up. But nevertheless, I still have my study-guides. With practice and motivation I’ll have no problem acing the test. The professor showed us some really cool geometric origami. They were made using the methods of tessellation and formed different geometric-patterns. It’s amazing how creative children’s minds can be. They can perceive certain aspects that teachers would otherwise not have noticed.

We also had some very unusual class-room presentations. One presentation involved candies which covered the topics of geometry and building a ginger-bread house.  Every child loves to make ginger-bread houses. Although it’s a shame we never really got to make one. But at least we still got some candies. Then there was another presentation where the student brought in a pet iguana (or is it a lizard?). She covered the topics of measurements and measured the lizard’s lengths. This is an excellent teaching-method because children love it when there are animals around.

Here is another ginger-bread house activity:
  • Gingerbread Houses
    • Gingerbread Geometry: challenge students to find the footprint, perimeter, surface area and volume of their proposed gingerbread houses before actual construction begins. If students are covering milk cartons, small groups could use empty cartons to find the measurements and describe the tools they used for each item. Have students use customary (in.) or metric (cm.) measurements, depending on teacher choice. Volume will be a challenge to younger students but they might fill the carton with water, rice or sand and then calculate how many cm-cubes or inch-cubes would fill the same number of cups to get an estimated volume. They could also fill the house with cm-cubes if a good supply is available. Students could leave the measurement in cups, if they are studying liquid measurements.
    • Decorating on a budget: Price candy decorations and allow students a certain budget to purchase decorating supplies. Allow students to plan out their house before actually constructing it.
    • Patterns: encourage students to use patterns for the roof and for walkways. Students should classify the patterns as AB, AAB, etc.
    • Tessellations: which candies tessellate the house surfaces by covering the entire surface without gaps or overlaps? 


Monday, November 26, 2012

Tessellations


Today we did some Geogebra activities. Following the procedures on work-sheets, we traced the angles along the x and y-axis and created a triangle. We then drew a second triangle using this weird method by clicking a button that enables us to make a copy of the triangle that originates from a certain point. We then did the same thing for the second activity only this time we had to make a reflection of the angle across the x-axis. The last work-sheet was the most confusing. Following the procedures, we had to draw a new triangle and then find the pre-images and reflections of each of the x and y-axis. On another table we had to find the x and y-coordinates using the horizontal line-slider and the vertical line-slider. I was really stumped because it was also confusing. I had to keep track of which triangles were the original and second triangles.

The professor showed us some art-works about tessellation. There were images made up of similar patterns that it was almost like an optical illusion. She also showed us a math video from “Cyberchase.” The topic was about tessellation. In this video an artist finds how he can move around similar objects to create a large object. But they all must be the same shape and they cannot over-lap or form gaps. Tessellation is a pattern made by repeating a regular polygon. They can be moved around using translation, rotation, and reflection.

http://www.mathsisfun.com/geometry/tessellation.html
Here is a very helpful link that further explains the methods of tessellation. There are different shapes and patterns. Notice how they are allowed to have more than one shape.
http://www.mathsisfun.com/geometry/tessellation.html
  

This is a really cool slide-show on tessellations:

Wednesday, November 21, 2012

Geometry Transformations


Today in class we went over the concepts of reflections, translations, and rotations. We did activity sheets and drew out the shapes and lines on grid-sheets. The translation part was easy. All we had to do was follow along the x and y-axis to form the new shapes. We then did the reflection activity. The center-points were based on wherever the problems said they were located along the x and y-axis. For instance, if the problem says to reflect along the x-axis then we draw the center line vertically. If the problem states to reflect along the y-axis then we draw the center line horizontally.

The rotation activity was pretty tricky. We had to figure out where the shapes would be located along the x or y-axis based on whether they are rotated 90 or 180 degrees clockwise or counterclockwise. The trick is we have to turn the paper in whatever rotation the problem indicates to see the new image. We then have to use a patty paper. I’m still stumped on this part but I will eventually figure it out. The professor also showed us some videos that are related to the assignment. One video is called “Transformation” involving a guy being rotated, translated, and reflected (although you may need to create an account to watch this video): http://www.brainpop.com/math/geometryandmeasurement/transformation/preview.weml

Here is another video from the Denise Carter’s website (Smarty Bunch) called “Geometry Transformations.”



Here is the link: http://www.youtube.com/watch?v=X0hllwR2zL4
I recommend teachers use these videos because they are very helpful and even fun to learn about geometry.

I found a very helpful math website and I regularly use it for this class. It goes over the three main transformations of the shapes: rotation, reflection, and translation. Here it is:

Monday, November 19, 2012

Surface Areas and Volumes

Today we did some activities involving the surface areas of different shapes. Some of the shapes included prisms, spheres, cylinders, and cones. We went over the formulas and then solved them based on the information given for each shape. Many of the formulas included Pythagorean theorems so find the missing sides of each shape. Some of the answers were solved in base squares. Others had the pie symbols or were solved by incorporating the pie formula with the answers. We also went over the formulas for the volume of the shapes.

We did a class-group activity about the volumes of pyramids and cones. We had to find the relationship between the volume of a pyramid and a prism and then we had to find the relationship between a cone and a cylinder. We used scissors and tapes to cut out and put together the shapes. We then filled the pyramid-shape with rice and compared its volume with the square-prism. We did the same thing with the cone and cylinder. The results were mostly the same. The pyramid and the cone were both 1/3 the volume of the square-prism and the cylinder. Students will enjoy this activity and find it easier to understand the concepts of different volumes.

Here is a very helpful video on evaluating formulas of volume of different shapes:


Students can refer to this website for volume formulas of different shapes:

Thursday, November 8, 2012

Rubber Bands and Picks


On Wednesday we went over the concepts of measurement and area. We did an activity sheet that showed pictures of pins and lines forming geometric patterns. We had to count the number of squares and outer pins that formed the geometric shapes. We used the number of squares to find the area and the number of outer pins to find the perimeter of the geometric shapes. We also did a classroom activity involving rubber bands and pins. By stretching around the rubber bands we were able to form geometric shapes. We then applied the same method from the activity sheet to count the number of squares and outer pins. We also went over the concept of Pick’s Theorem.

Pick’s Theorem is A = 1/2 x P – 1

Example:

If a geometric figure has a perimeter of 8 pins, what is the area of the geometric figure?
A = ½ x 8 + 2 – 1
A = (1/2 x 8) + 2 – 1
A = 4 + 2 – 1
A = 6 – 1
A = 5
The area is 5 or I have 5 squares in the geometric figure.

Another method is A = ½ P + I – 1
The I stand for the interior pins that are inside of the geometric figures.

I found a website that further explains Pick’s Theorem. Notice that some of the letters have been changed around but they still apply the same concepts:

I also found a very helpful video that demonstrates the process of Pick’s Theorem:


From this lesson I learned a different method on how to find the areas and perimeters of geometric figures. The activities taught me how the figures can be broken up into squares, triangles, and trapezoids. I really enjoyed doing the rubber-band activity. It helped me get a better grasp of the concepts. Children will also find this activity fun and because they are more actively involved. This is an excellent activity for students who are visually disoriented, visual, or hands-on-learners.