This short video and interactive assessment activity is designed to teach third graders about choosing the multiples of a given number up to 12.
This task suggests methods of introducing and continuing choral counting in the classroom.
Teachers (and then students) lead the class in chanting numbers from 1 to 120.
The purpose of this task is for students to find different pairs of numbers that sum to 7.
This task is primarily about volume and surface area, although it also gives students an early look at converting between measurements in scale models and the real objects they correspond to.
This video explains how cicadas emerge every 13 or 17 years, which are prime numbers.
Students apply and interpret their understanding of area in a real world situation.
Although this task is fairly straightforward, it is worth noticing that it does not explicitly tell students to look for intersection points when they graph the circle and the line. Thus, in addition to assessing whether they can solve the system of equations, it is assessing a simple but important piece of conceptual understanding, namely the correspondence between intersection points of the two graphs and solutions of the system.
Proportionality between circumference, angle and arc length; area, angle and area of sector. Circumference and area of circle equation, Image of four circles with hotpots of calculations
Angle of sector or arc is proportional to the circumference or area of total circle. Interactive drag and drop factor to use when calculating arc length or sector area.
Slides showing steps to derive the equation of a circle, using the Pythagorean Theorem
Slides showing steps to solve for center and radius of a circle given an equation of a circle by completing the square.
In this Nrich problem students build on their existing knowledge of proportions to build a function in an engaging context.
This task shows that the three perpendicular bisectors of the sides of a triangle all meet in a point, using the characterization of the perpendicular bisector of a line segment as the set of points equidistant from the two ends of the segment. The point so constructed is called the circumcenter of the triangle.
An interactive applet and associated web page that demonstrate the circumference of a circle. The applet shows a circle with a radius line. The radius endpoints are draggable and the circle is resized accordingly. The formula relating radius to circumference is updated continually as you drag. Introduces the idea of Pi. The formula can be hidden for class discussion and estimation. See also the entries for circumference and diameter. See also entries for radius and diameter. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.
This short video and interactive assessment activity is designed to give fourth graders an overview of angles.
This short video and interactive assessment activity is designed to teach third graders about classifying all types of triangles by lengths of sides.
This short video and interactive assessment activity is designed to teach fourth graders about classifying all types of triangles by lengths of sides.
This short video and interactive assessment activity is designed to teach third graders an overview of triangle classifications.
This short video and interactive assessment activity is designed to teach third graders about classifying triangles based on equal sides.