Maths Challenge
Maths challenge.net: Corner Circle
This is a "three star" geometry problem where prior knowledge of circles and triangles is recommended to solve this circle in the corner problem.
Maths Challenge
Maths challenge.net: Unique Circle Equal Angles
A "three star geometry problem" - requiring the knowledge of biconditional statements and how to prove such problems.
Maths Challenge
Maths challenge.net: Lunes
A "three star" geometry problem where some experience of math problem solving skills and knowledge of circles is recommended to solve this lunes (parts of a circles) area problem
Maths Challenge
Maths challenge.net: Inscribed Rectangle
This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles to solve this equal area of inscribed polygons problem.
Maths Challenge
Maths challenge.net: Isosceles Trapezium
This is a "three star" geometry problem where prior knowledge of problem solving and thinking through proofs is recommended to solve this trapezoid inscribed in a semicircle problem.
Curated OER
Eternal Egypt: Seal With an Ornamental Star
A circular clay seal, which was probably used in the church, to stamp objects and to bless them.
Maths Challenge
Maths challenge.net: Children in a Circle
A "one star" geometry problem that requires problems solving skills where drawing a picture might help with the answer.
University of Cambridge
University of Cambridge: Nrich: Round and Round the Circle
Learn multiplication with this dial star exercise. Predict what shapes you will get with different numbers.
Science Buddies
Science Buddies: How Big Are the Planets in Our Solar System?
This activity explores the relative size of the eight planets that circle around the Sun.
Maths Challenge
Maths challenge.net: Cables
This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles to solve this problem with cables in duct problem.
Maths Challenge
Maths challenge.net: Radical Axis
This is a "three star" geometry problem requiring knowledge of proofs and properties of circles. Students will use the given definition of radical axis and prior knowledges to prove a way to find a radical axis.
Scholastic
Scholastic: Max's Math Adventures: Max's Fantastical Zoo
Use this rhyming description of Max's Fantastical Zoo to make some amazing animals from geometric shapes. There is a teacher's guide for easy lesson planning.
Other
Paper Plate Education: Serving the Universe on a Paper Plate
Excellent resource for "paper-plate" activities that help simplify various astronomy topics. Learn how to build a "Moon Finder" and "Planet Pointer," and create a paper-plate model that explains the Transit of Venus.
Curated OER
Etc: Maps Etc: The United States Population and Railroad Network, 1901
A map from 1901 of the United States showing population density, railroad lines, state capitals, and census centers of population at the time. The red figures indicate the mean population density per square mile for each state according...
Curated OER
Eternal Egypt: Marble Molding
This round marble ornament is decorated with a raised carved circle consisting of six cups with double interlaced branches from a six-headed star.