Lesson Notes By Weeks and Term v4 - SHS 3
SPATIAL SENSE
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SPATIAL SENSE
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Subject: Mathematics
Class: SHS 3
Term: 2nd Term
Week: 7
Grade code: 3.3.1.LI.2
Strand code: 3
Sub-strand code: 1
Content standard code: 3.3.1.CS.2
Indicator code: 3.3.1.LI.2
Theme: GEOMETRY AROUND US
Subtheme: SPATIAL SENSE
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This lesson focuses on the practical skill of geometric construction. Spatial sense is not just about abstract shapes; it's about understanding and creating them accurately in the real world. In Ghana, this skill is fundamental for many professions, from the artisan who designs beautiful Kente patterns to the architect who draws the plan for a new house in Accra, and the surveyor who demarcates a plot of land for farming in the Volta Region. Today, we will learn the precise steps to construct triangles and quadrilaterals using basic geometric tools, which is the foundation of technical drawing and design.
The core idea of geometric construction is to draw shapes that meet specific measurements of length and angles. Accuracy is key. We will rely on our tools: the ruler for measuring lengths, the protractor for measuring angles, and the compass for drawing arcs of a specific radius.
A good construction starts with a rough sketch of the final shape. This helps you to plan your steps and visualise the outcome. A. Constructing Triangles
There are several standard cases for constructing a unique triangle.
Case 1: Given Two Sides and the Included Angle (SAS) The "included angle" is the angle *between* the two given sides.