Are Random Triangles Acute or Obtuse?

This learning video deals with a question of geometrical probability. A key idea presented is the fact that a linear equation in three dimensions produces a plane. The video focuses on random triangles that are defined by their three respective angles. These angles are chosen randomly subject to a constraint that they must sum to 180 degrees. An example of the types of in-class activities for between segments of the video is: Ask six students for numbers and make those numbers the coordinates x,y of three points. Then have the class try to figure out how to decide if the triangle with those corners is acute or obtuse.

Material Type: Lecture

Author: Gilbert Strange

Using Geometry to Design Simple Machines

This video is meant to be a fun, hands-on session that gets students to think hard about how machines work. It teaches them the connection between the geometry that they study and the kinematics that engineers use -- explaining that kinematics is simply geometry in motion. In this lesson, geometry will be used in a way that students are not used to. Materials necessary for the hands-on activities include two options: pegboard, nails/screws and a small saw; or colored construction paper, thumbtacks and scissors. Some in-class activities for the breaks between the video segments include: exploring the role of geometry in a slider-crank mechanism; determining at which point to locate a joint or bearing in a mechanism; recognizing useful mechanisms in the students' communities that employ the same guided motion they have been studying.

Material Type: Lecture

Authors: Daniel D. Frey, MIT BLOSSOMS

AAS Congruent Triangles

An interactive applet and associated web page that shows how triangles that have two angles and a non-included side the same must be congruent. The applet shows two triangles, one of which can be reshaped by dragging any vertex. The other changes to remain congruent to it and the two angles and non-included side are outlined in bold to show they are the same measure and are the elements being used to prove congruence. The web page describes all this and has links to other related pages. 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.

Material Type: Reading, Simulation

Author: John Page

The Pythagorean Theorem: Square Areas

This lesson unit is intended to help teachers assess how well students are able to: use the area of right triangles to deduce the areas of other shapes; use dissection methods for finding areas; organize an investigation systematically and collect data; deduce a generalizable method for finding lengths and areas (The Pythagorean Theorem.)

Material Type: Assessment, Lesson Plan

Inscribed Angles That Intercept the Same Arc

If two inscribed angles intercept the same arc, then the angles are equal. Drag the orange points to change the figure.

Material Type: Activity/Lab, Diagram/Illustration, Homework/Assignment, Interactive, Simulation, Teaching/Learning Strategy

Author: Jay Warendorff

Modeling: Having Kittens

This lesson unit is intended to help teachers assess how well students are able to: interpret a situation and represent the constraints and variables mathematically; select appropriate mathematical methods to use; make sensible estimates and assumptions; investigate an exponentially increasing sequence; and communicate their reasoning clearly.

Material Type: Assessment, Lesson Plan

Taking Walks, Delivering Mail: An Introduction to Graph Theory

This learning video presents an introduction to graph theory through two fun, puzzle-like problems: ''The Seven Bridges of Konigsberg'' and ''The Chinese Postman Problem''. Any high school student in a college-preparatory math class should be able to participate in this lesson. Materials needed include: pen and paper for the students; if possible, printed-out copies of the graphs and image that are used in the module; and a blackboard or equivalent. During this video lesson, students will learn graph theory by finding a route through a city/town/village without crossing the same path twice. They will also learn to determine the length of the shortest route that covers all the roads in a city/town/village. To achieve these two learning objectives, they will use nodes and arcs to create a graph and represent a real problem.

Material Type: Lecture

Authors: BLOSSOMS, Karima R. Nigmatulina

Points Equidistant from Two Points in the Plane

This task is part of a series presenting important foundational geometric results and constructions which are fundamental for more elaborate arguments. They are presented without a real world context so as to see the important hypotheses and logical steps involved as clearly as possible.

Material Type: Activity/Lab

Author: Illustrative Mathematics

How Many Cells are in the Human Body?

The purpose of this task is for students to apply the concepts of mass, volume, and density in a real-world context. There are several ways one might approach the problem, e.g., by estimating the volume of a person and dividing by the volume of a cell.

Material Type: Activity/Lab

Author: Illustrative Mathematics

CTE Health Sciences: Range of Motion

This task was developed by high school and postsecondary mathematics and health sciences educators, and validated by content experts in the Common Core State Standards in mathematics and the National Career Clusters Knowledge & Skills Statements. It was developed with the purpose of demonstrating how the Common Core and CTE Knowledge & Skills Statements can be integrated into classroom learning - and to provide classroom teachers with a truly authentic task for either mathematics or CTE courses.

Material Type: Activity/Lab, Lesson Plan

Pythagoras and the Juice Seller

This video lesson presents a real world problem that can be solved by using the Pythagorean theorem. The problem faces a juice seller daily. He has equilateral barrels with equal heights and he always tries to empty the juice of two barrels into a third barrel that has a volume equal to the sum of the volumes of the two barrels. This juice seller wants to find a simple way to help him select the right barrel without wasting time, and without any calculations - since he is ignorant of Mathematics. The prerequisite for this lesson includes knowledge of the following: the Pythagorean theorem; calculation of a triangles area knowing the angle between its two sides; cosine rule; calculation of a circle's area; and calculation of the areas and volumes of solids with regular bases.

Material Type: Lecture

Author: Ghada Sulaiman Abdullah Marmash

Magic Eyes

Our glasses are designed to convert images that are 2-dimensional into 3-dimensional images

Material Type: Lesson

Authors: Dee Anderson, Hanan Salah, sana rashed, Mayson Abuhamda

Islamic Art and Culture: A Resource for Teachers

In this packet we look at works that span nearly a thousand yearsäóîfrom shortly after the foundation of Islam in the seventh century to the seventeenth century when the last two great Islamic empiresäóîthe Ottoman and the Safavidäóîhad reached their peak. Although the definition of Islamic art usually includes work made in Mughal India, it is beyond the scope of this packet. The works we will look at here come from as far west as Spain and as far east as Afghanistan.

Material Type: Reading, Teaching/Learning Strategy

Maths and Islamic art & design

This resource provides a variety of information and activities that teachers may like to use with their students to explore the Islamic Middle East collections at the V&A. It can be used to support learning in Maths and Art. Included in this resource are sections on: Principles of Islamic art and design Pre-visit activities Activities to do in the museum Activities to do back at school Islamic art explores the geometric systems that depend upon the regular division of the circle and the study of Islamic art increases appreciation and understanding of geometry. The use of these geometric systems creates a harmony among Islamic decorative arts and architecture, which is consistent with the Islamic belief that all creation is harmoniously interrelated. Approaching an abstract subject in a concrete way provides a means of extending maths into other curriculum areas. The context of the Museum expands and enriches students' appreciation of the application of geometry in a cultural context and develops the sense of different cultural identities. Students have the opportunity to become familiar with the relationship between geometry and design and this can give confidence to students who have never seen themselves as 'good at art'.

Material Type: Activity/Lab, Diagram/Illustration

Ilkhanid Mihrab

This art history video discussion examines the "Mihrab" (prayer niche), 1354--55 (A.H. 755), just after the Ilkhanid period, Isfahan, Iran, polychrome glazed tiles, 135-1/16 x 113-11/16 inches / 343.1 x 288.7 cm (Metropolitan Museum of Art, New York).

Material Type: Diagram/Illustration, Lecture

Authors: Beth Harris, Steven Zucker

Congruent Segments

Students' first experience with transformations is likely to be with specific shapes like triangles, quadrilaterals, circles, and figures with symmetry. Exhibiting a sequence of transformations that shows that two generic line segments of the same length are congruent is a good way for students to begin thinking about transformations in greater generality.

Material Type: Activity/Lab

Author: Illustrative Mathematics

Wallpaper Tessellations

In this video segment from Cyberchase, Harry uses tessellations to wallpaper his apartment. ***Access to Teacher's Domain content now requires free login to PBS Learning Media.

Material Type: Lecture

Authors: U.S. Department of Education, WNET

A-CED Regular Tessellations of the plane

This task examines the ways in which the plane can be covered by regular polygons in a very strict arrangement called a regular tessellation. These tessellations are studied here using algebra, which enters the picture via the formula for the measure of the interior angles of a regular polygon (which should therefore be introduced or reviewed before beginning the task). The goal of the task is to use algebra in order to understand which tessellations of the plane with regular polygons are possible.

Material Type: Activity/Lab

Author: Illustrative Mathematics

Everything Maths: Grade 10

This is a comprehensive math textbook for Grade 10. It can be downloaded, read on-line on a mobile phone, computer or iPad. Every chapter has links to on-line video lessons and explanations. Summary presentations at the end of each chapter offer an overview of the content covered, with key points highlighted for easy revision. Topics covered are: algebraic expressions, equations and inequalities, exponents, number patterns, functions, finance and growth, trigonometry, analytical geometry, statistics, probability, Euclidean geometry, measurements. This book is based upon the original Free High School Science Text series.

Material Type: Textbook

Modeling and Simulation for High School Teachers: Principles, Problems, and Lesson Plans

A collaboration between the National Aeronautics and Space Administration (NASA) and the CK-12 Foundation, this book provides high school mathematics and physics teachers with an introduction to the main principles of modeling and simulation used in science and engineering. An appendix of lesson plans is included.

Material Type: Lesson Plan, Teaching/Learning Strategy, Textbook