42Explore– https://42explore.com/geomet.htm – This resource is excellent because it provides both “Easy” and “Harder” descriptions for the various aspects of geometry.
BetterLesson – https://betterlesson.com/ – Lesson ideas in the Math section with the subheadings specified below.
Calculator.net – https://www.calculator.net/conversion-calculator.html – Use it to convert between commonly used units. Select the current unit in the left column, the desired unit in the right column and enter a value to generate the resulting conversion.
CanFigureIt Geometry – https://www.canfigureit.com/ – An interactive canvas to make and prove claims. A continuously updated diagram indicating where students are in the proof. An embedded glossary with visuals and templates demonstrating the structure of theorems. A teacher dashboard that provides performance reports at the student and classroom level.
Dad’s Worksheets – https://www.dadsworksheets.com/ – There are only a few worksheets aimedspecifically at geometry or measurement on this website.
Measurement Chart – This measurement chart is a good reference aid for word problems involving converting volume, length or temperature units from one system to the other. Values are shown on one scale in both customary and metric systems.
Slope Calculator – Takes two points, uses the slope formula to calculate the slope of a line defined by those two points and then the y intercept. The slope and the intercept are combined to provide the equation of the line in slope intercept form.
Coordinate Plane – The blank coordinate planes include variations with labels on either the axis or the edge of the grid, as well as versions with quadrant labels.
Degrees to Radians Converter – Calculates complementary and supplementary angles; shows a combined representation of the related angles so that they can be immediately visualized. The calculator automatically converts from degrees to radians when you enter a new value.
eTAP – https://www.etap.org – Brings quality personalized education to children throughout the country with whatever educational resources can best engage them and promote active learners.
Galileo Educational Network – https://galileo.org/math-investigations – A list of seconday school classroom resources for shape and space. The list is very short:
Area is a Square Deal – If we measure the area of rectangles by dividing them into squares, then what shape should we use to measure area for triangles?
Connect The Dots– A unicursal curve in the plane is a curve that you get when you put down your pencil, and draw until you get back to the starting point.
Tiling – Determining what shapes tile a plane is not a simple matter. There are some polygons that will tile a plane and other polygons that will not tile a plane.
Edx – https://www.edx.org/course/subject/math – Online math courses from MIT, ASU, and other leading math and science institutions. Get introductions to algebra, geometry, trigonometry, precalculus and calculus or get help with current math coursework and AP exam preparation.
Geogebra– https://www.geogebra.org/ – Free digital tools for class activities, graphing, geometry, collaborative whiteboard and more. Find over 1 million free activities, simulations, exercises, lessons, and games for math.
Gizmos– https://www.explorelearning.com/ – Find the perfect Gizmo to get your students ready for success. Manage your classes and assess your grade 3-12 students in one place. Make planning easy with customizable, expert lesson materials.There are free gizmos available but access to the full library needs a subscription.
Inside Mathematics – https://www.insidemathematics.org/common-core-resources/high-school-geometry – Find all high school geometry resources to guide and support mathematics teaching and learning. These resources are organized by mathematical strand and refer to specific Common Core math content standards.
iSmartboard.com – Use these Smart Board games, activities and lessons to learn about Radius, Diameter, Shapes, Quadrilaterals in grade 7-8 and Calculus, Algorithms, Differential, Fractals, Matrix, Pre-Calculus and Trigonometry in grade 9+. Note: Lots of ads to deal with on the page.
Khan Academy – https://www.khanacademy.org/ – The most fundamental branch of math is having a clear idea on number sense and numeration. It consists of understanding place values and basic operations.
MIT Open Courseware – https://ocw.mit.edu/high-school/ – Highlights for High School contains an abundance of resources that cover not only science and mathematics but also engineering, humanities, and social sciences. These resources are available under a Creative Commons license, so the material on the site can be integrated into classroom lesson plans, shared, reused, and remixed.
National Centre for Excellence in the Teaching of Mathematics – The materials below are specifically for teachers dealing with numeracy.
PBS Learning Media – Explore the properties of angles, shapes, and figures in space. Angles are analyzed using pool balls in an interactive lesson and video, students can discover how using concentric circles can help determine how much paint is needed to cover the deck of a carousel and volume is analyzed through experiments with popcorn and meatballs. Make sure to use the filter to isolate the right grade.
Pink Monkey– http://www.pinkmonkey.com/studyguides/subjects/geometry/contents.asp – Nine geometry-packed chapters that include lessons, quizzes, and more. The website’s simple design and easy-to-navigate chapters make it easy to interact with.
School Yourself – https://schoolyourself.org/learn/calculus and https://schoolyourself.org/learn/trigonometry – Interactive video lessons on calculus and trigonometry. Calculus: the mathematics of change and it’ll use just about every branch of math you’ve learned before it. Trigonometry helps you understand any topic that involves distances, angles, or waves. The trig functions (sin, cos, and tan) show up all over science and engineering.
Super Teacher Worksheets– https://www.superteacherworksheets.com/ –Various types of shape and space worksheets available including angles, area, perimeter, shapes, radius, and more. The limited amount of “free” worksheets on this subject are listed below:
Texas Instruments – https://education.ti.com/en/activities – Browse and download activities designed for the complete line of Texas Instruments (TI) graphing calculators. Here are the search results from the activities directory for gr. 10-12 students:
The Centre for Education in Mathematics and Computing – https://courseware.cemc.uwaterloo.ca/ – Covers the topics typically taught in Canadian Grade 7 – 9 Mathematics curricula and, in some instances, extends ideas beyond grade level.
Grade 12 Advanced Functions and Pre-Calculus:Students will investigate the properties of polynomial, rational, exponential, logarithmic, trigonometric and radical functions; develop techniques for combining functions; broaden their understanding of rates of change; and develop facility in applying these concepts and skills.
Grade 12 Calculus and Vectors: Students will extend their understanding of rates of change to include the derivatives of polynomial, rational, exponential, logarithmic, and trigonometric functions; and they will apply these to the modelling of real-world relationships. Integral calculus and its applications will be introduced. Students will solve problems involving vectors and lines and planes in three-space.
The Get-it Guide – Math tutorials with slideshows and a follow-up worksheet to help focuson the key steps required for solving the math problem, determine the steps of the solution path you understand and identify the steps of your solution path you do not yet understand. Develop mathematical resilience when solving problems. Read and talk about the math problem you are trying to solve.
The Math Learning Center – https://www.mathlearningcenter.org/apps – The apps are based on visual models featured in Bridges in Mathematics. They are available in two or more versions: a web app for all modern browsers, and downloadable versions for specific operating systems and devices (such as Apple iOS for iPad).
Virtual Nerd – https://www.virtualnerd.com/ – Developed as a supplemental learning resource for teachers and students with over 1,500 video lessons focusing on middle school and high school mathematics – especially for algebra and geometry.
Visual Calculus– Visual Calculator – This site contains explanations, tutorials, and animations covering the following topics: limits and continuity, derivatives, applications of differentiation, integration, applications of integration, and sequences and series.
Visual Fractions – https://visualfractions.com/ – A way to help students learn about fractions and to understand them using interactive visual tools. Since then, we have expanded to become an online reference – covering fraction and math calculators, percentages, unit conversions, and more.
42Explore – https://42explore.com/geomet.htm – This resource is excellent because it provides both “Easy” and “Harder” descriptions for the various aspects of geometry. 
eTAP – https://www.etap.org – Brings quality personalized education to children throughout the country with whatever educational resources can best engage them and promote active learners. 