Identify Acute Right and Obtuse Angles-Gr 4.pdf

4.6Measurement: Blocks, Corners, and IntersectionsFocal PointMeasurement – Identify angles whose measure isgreater than or less than a right angle. Use the wordsobtuse, acute, and right in relation to angles.Materials• Pattern blocks• One of eachStudents then investigate the angles of the other patternblocks and record their answers on the worksheet.Guided Learning1. How many shapes have right angles? Acute angles?Obtuse angles?2. Can a shape have both acute angles and obtuseangles? Explain.InstructionsHave the students place the corner of the orange patternblock at the intersection of the two dotted lines on theworksheet. Tell them that these lines intersect to formright angles.Ask: How many right angles does the square contain? Doany of the other pattern blocks have right angles? (Onthe worksheet, the number of right angles in a square isalready filled in.)Tell students that angles with a measure greater thana right angle are called obtuse angles; angles with a measureless than a right angle are called acute angles.Next, have the students compare a right angle in thesquare pattern block with an angle in the hexagon. Theydo this by placing one angle over another, making sureone edge of the two pattern blocks is lined up.Ask: Is Angle 1 on the hexagon greater than a right angleor smaller?It is greater.Have the students look next at Angle 2 and so on. In thespace next to the hexagon, they describe the angles theyfound.Explore More!Using 1, 2, 3, or 4 pattern blocks, can you construct oridentify a figure with fewer than 3 angles? Why or whynot?78 – Advanced Pattern Block Book © Didax – www.didax.com