Grade: Grade 9  
Type: ODE Model Lesson Plans
Description: Students will find the height of an object that would be difficult or impossible to measure directly. They will construct and use a clinometer to measure the angle of elevation (or depression). Students will create a sketch of the measurement situation using a right triangle, indicate relevant points in the physical situation, and use basic trigonometric ratios to calculate the desired lengths.  
Ohio Standards Connection:
Primary Standards, Benchmarks, and Indicators:
Standard:  Measurement
  Benchmark: D.  Use proportional reasoning and apply indirect measurement techniques, including right triangle trigonometry and properties of similar triangles, to solve problems involving measurements and rates.
  Indicator: 4.  Use scale drawings and right triangle trigonometry to solve problems that include unknown distances and angle measures.
Standard:  Mathematical Processes Standard
  Benchmark: A.  Formulate a problem or mathematical model in response to a specific need or situation, determine information required to solve the problem, choose method for obtaining this information, and set limits for acceptable solution.       
Secondary Standards, Benchmarks and Indicators:
Standard:  Measurement
 Benchmark  C.  Apply indirect measurement techniques, tools and formulas, as appropriate, to find perimeter, circumference and area of circles, triangles, quadrilaterals and composite shapes, and to find volume of prisms, cylinders, and pyramids.
Standard:  Geometry and Spatial Sense
 Benchmark  H.  Establish the validity of conjectures about geometric objects, their properties and relationships by counter-example, inductive and deductive reasoning, and critiquing arguments made by others.
 Benchmark  I.  Use right triangle trigonometric relationships to determine lengths and angle measures.