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Unit 3 Fifth Grade
Unit Goals Determine angle measures based on relationships between angles. Estimate the measure of an angle. Measure an angle to within 2°. Identify types of angles. Identify types of triangles. Identify place value in numbers to billions. Know properties of polygons. Define and create tessellations.
Determine angle measures based on relationships between angles. You can use your knowledge of angles to estimate angle measures. Remember- a circle is 360°, a straight line is 180°
For example: I know that this is a right triangle next to a square. The square’s corner measures 90°, and the angle of the triangle is about half that. Together, the angle should measure about 90 + 45, or 135° What is the measure of this angle?
What is the measure of this angle? 180 ° 225 ° 240 ° 150 °
Correct! This angle measures 240°.  You can know this because: -  the angles in the equilateral triangles are each 60° (60 + 60= 120)  the corner of the parallelogram could be made up using two equilateral triangles (60 + 60 = 120)  for a combined total of 240°.  60° 60° Far Out! Click me to go back to the goals page.
Keep Trying! This angle measures 240°.  You can know this because: -  the angles in the equilateral triangles are each 60° (60 + 60= 120)  the corner of the parallelogram could be made up using two equilateral triangles (60 + 60 = 120)  for a combined total of 240°.  60° 60° Read through the description carefully- click to go back to the explanation page.
Estimate the measure of an angle. Think about the angle in relationship to 90° 90° 90° 90° 90° A complete circle is 360° A half circle (or straight line) is 180° A quarter circle is 90° If an angle is acute, it will be less than 90° If an angle is obtuse, it will be between 91°   -179° If the angle is a straight line, it will be equal to 180°
Estimate the measure of an angle. Which of these angles is equal to about 175°? A B C D
Correct! A This angle is closest to 175°. - It is slightly less than 180° (which is a straight line) Groovy! Click me to GO for the GOALS.
Keep Trying! A This angle is closest to 175°. - It is slightly less than 180° (which is a straight line) You might want to read the description more carefully.  Ask for help if you still need it.
Measure an angle to within 2° For practice with this skill, visit: http://www.amblesideprimary.com/ambleweb/mentalmaths/protractor.html If you need a protractor, you can print one up at: http://www.ossmann.com/protractor/conventional-protractor.pdf   * Make sure you line your protractor up carefully! Click me to go back to the goals page.
Identify types of angles A  right  angle is 90°.  It looks like the corner of your paper or the letter L. An  acute  angle is LESS THAN 90°.  It is a cute little angle   . An  obtuse  angle is MORE THAN 90° A  reflex  angle is MORE THAN 180°
Try One! A B C D E F Which of these is an obtuse angle? <ABC <ABE <ABF <FCD
CORRECT! A B C D E F <ABF is  obtuse  because it measures more than 90° but less than 180°.  Awesome Work!  Click me to go back to the goals.
Try Again! A B C D E F <ABF is  obtuse  because it measures more than 90° but less than 180°.  <ABE is a  straight angle  because it measures exactly 180°.  Stick with it- Click me to go back to the explanation.
Identify types of triangles Meet the triangle family I’m Evelyn  Equilateral , and I’m always worried that everything should be equal.  I have  three equal sides  and  three equal angles . I’m Ivan  Isosceles  and while I’m not as equal as an equilateral triangle, I do still have  two equal sides  and  two equal angles. We’re Roger and Randy Right- The Right Brothers!  We like to think that we’re always right, but really we’re called  right  triangles because we both have a  right angle that measures 90°. That’s right, but one thing my brother Randy forgot to mention is that I’m a special right triangle.  I take after the Isosceles side of the family because not only do I have a  right angle , I also have  two other equal angles and sides .  That makes me a  Right Isosceles  triangle. I’m Salvador  Scalene .  I’m the oddball of the family-  I don’t have any equal sides or angles.
Equilateral Right Isosceles Right Isosceles Scalene Can you name us?
Try One! Click on the  scalene  triangle.
Correct! That’s right, another odd-ball.  This triangle is  scalene  because it has  no equal sides or angles. Click for the next problem.
Try Again! This triangle is  scalene  because it has  no equal sides or angles. Click for the next problem.
Try One! Click on the  right isosceles  triangle.
Correct! That’s right, this is a  right isosceles  triangle.  This triangle is  isosceles  because it has  two equal sides and angles.  It is  right  because it has a  90° angle . Click for the next problem.
Try Again! This is a  right isosceles  triangle.  This triangle is  isosceles  because it has  two equal sides and angles.  It is  right  because it has a  90° angle . Click for the next problem.
Try One! Click on the  isosceles  triangle.
Correct! That’s right, this is an  isosceles  triangle.  This triangle is  isosceles  because it has  two equal sides and angles.   Click for the next problem.
Try Again! This is an  isosceles  triangle.  This triangle is  isosceles  because it has  two equal sides and angles.   Click for the next problem.
Try One! Click on the  equilateral  triangle.
Correct! That’s right, this is an  equilateral  triangle.  This triangle is  equilateral  because it has  all equal sides and angles.   Click for the next problem.
Try Again! This is an  equilateral  triangle.  This triangle is  equilateral  because it has  all equal sides and angles.   Click for the next problem.
Try One! Click on the  right  triangle.
Correct! That’s right, this is a  right  triangle.  This triangle is  right  because it has  a 90° angle.   Click me to go to the goals.
Try Again! That’s right, this is a  right  triangle.  This triangle is  right  because it has  a 90° angle.   Click me to go back to the explanation.
Identify place value in numbers to billions For each set of three, there is a pattern of units, tens, and hundreds.  Remember that when naming numbers, you name each group of three.  For example, the number above is one billion, three hundred fifty four million, two hundred six thousand, five hundred ninety nine. Notice that when you name numbers, the only time you use the word “and” is when you are referring to a decimal point.  For example, 5.2 is five  and  two tenths.  NOT  five point two. 9 9 5 6 0 2 4 5 3 1 Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions
Try One! Which digit is in the hundred thousands place? 3 2 7 0 9 8 7 6 0 2 4 5 3 1
Correct! Which digit is in the hundred thousands place? 3 2 7 0 Click for the next problem Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Try Again! Which digit is in the hundred thousands place? 3 2 7 0 Click for the next problem Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Try One! Which digit is in the ten millions place? 5 8 4 0 9 8 7 6 0 2 4 5 3 1
Correct! Which digit is in the ten millions place? 5 8 4 0 Click for the next problem Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Try Again! Which digit is in the ten millions place? 5 8 4 0 Click for the next problem Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Try One! Which digit is in the billions place? 3 5 4 1 9 8 7 6 0 2 4 5 3 1
Correct! Which digit is in the billions place? 3 5 4 1 Click me to go to the goals. Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Try Again! Which digit is in the billions place? 3 5 4 1 Click me to go back to the explanation. Ones Tens Hundreds Thousands Ten thousands Hundred thousands Millions Ten millions Hundred millions Billions  9 8 7 6 0 2 4 5 3 1
Know properties of polygons A  polygon  is a plane shape having 3 or more sides. The number of degrees in a polygon depends upon the number of sides it has. The name of a polygon depends upon the number of sides it has and the relationship of those sides to one another.
Some examples of polygons… How many can you name? pentagon rectangle rhombus trapezoid square octagon hexagon Right triangle Equilateral triangle
Some polygon terms… A  regular  polygon has equal sides and angles. A  quadrilateral  describes any four-sided polygon. A  parallelogram  describes any quadrilateral with two sets of parallel sides of equal length with equal angles.
Naming Polygons The prefix in the name of a polygon indicates the number of sides it has. tri quad pent hex oct icosa 20 dodec 12 dec 10 non 9 hept 7 prefix Sides
Explore Polygons Check out the polygon playground! Learn more about figures and polygons. Click me to go back to the goals.
Define and create tessellations A  tessellation  is a  pattern  of shapes that has  no gaps  or  overlaps A  regular tessellation  is made up of regular polygons (polygons with equal sides and angles) Tessellations are described by listing the number of sides of the polygons around each vertex.
Examples of Tessellations Learn more about tessellations Try a think quest on tessellations Try making some tessellations! Tessellations can be a form of art.  Check out some galleries! To The Unit Goals Page Click HERE To Go Back