February/March Math Workshop

The fourth grade geometry unit will build upon the knowledge of geometry that the students were introduced to in third grade.  During this unit, we will be introducing points, lines, line segments, rays  as well as the relationship between them.  The students will be able to identify each of these both independently and within a shape.  Students will also learn how to properly use a protractor and use that knowledge to not only measure a given angle, but also construct their own angles.  Students will also learn to identify lines of symmetry within a shape and understand what makes two shapes congruent. We will focus on the classification of triangles by both length of sides and measurement of angles, and finally, we will look at other 2-D shapes and learn how to identify each by the number of sides.  See below for a comprehensive vocabulary list of terms that will be covered throughout this topic, as well as more detailed descriptions with sample problems.

Geometry Vocabulary:

• Acute angle - an angle that measures less than 90 degrees  
  
• Acute triangle - triangle with all interior angles that measure less than 90 degrees 
  
• Angle - the figure that is formed when two rays meet sharing a common vertex
  
• Degree - The unit used to measure angles 
  
• Equilateral Triangle - A triangle with three equal sides
  
• Intersecting Lines - Lines that cross at any given point
  
• Isosceles Triangle - Triangle with two equal sides
  
• Line - A straight path made up of points
  
• Line of Symmetry - The line through a figure that creates two halves that match exactly
  
• Obtuse Angle - An angle with a measure that is more than 90 degrees
  
• Obtuse Triangle - A triangle with one angle that is more than 90 degrees
  
• Parallel Lines - Lines that do not intersect
  
• Perpendicular Lines - Lines that form a right angle when they do intersect
  
• Point - Precise location along a line or plane
  
• Protractor - A tool used to measure angles
  
• Right Angle -  An angle that measures to exactly 90 degrees
  
• Right Triangle - A triangle that contains 90 degrees
  
• Scalene Triangle - A triangle with no equal sides or angles