National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Rhombus
This is a very brief look at the rhombus, which is a quadrilateral shape with four equal sides. Features include a JavaSketchpad that allows you to manipulate the shape.
CK-12 Foundation
Ck 12: Plix Series: Resonance: Metallic Bonding
[Free Registration/Login Required] Manipulate the electrons and protons to explore metallic bonding. Then answer a self-correcting concept question.
CK-12 Foundation
Ck 12: Plix Series: Resonance: Ozone Resonance
[Free Registration/Login Required] Explore resonance by manipulating the electrons and bonds, and then answer a challenge question about the concept.
CK-12 Foundation
Ck 12: Plix Series: Percent Composition
[Free Registration/Login Required] Manipulate graph data to see a representation of the percent composition of different compounds. Then answer a challenge question about the activity.
Texas Instruments
Texas Instruments: Similarity and Dilations
Students will discover properties of similar figures using the TI-89 and CABRI Geometry II to use dilations to dynamically manipulate figures.
Illustrative Mathematics
Illustrative Mathematics: G Gpe Slopes and Circles
The purpose of this task is to lead young scholars through an algebraic approach to a well-known result from classical geometry, namely, that a point X is on the circle of diameter AB whenever angle AXB is a right angle. This consists of...
National Council of Teachers of Mathematics
The Math Forum: Bricks Activity, Teacher Lesson Plan
Builders of brick walls need to be especially aware of fault lines which can easily lead to the collapse of the wall. Middle schoolers are challenged, here, to use polyminoes to design patterns for brick walls which do not contain fault...
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Measurement Inches
This lesson plan for primary students gives students hands-on practice in using a ruler and understanding customary measurements, length and width in inches. Students also create simple one and two digit addition problems related to the...
University of Cambridge
University of Cambridge: Nrich: Little Squares
What are square numbers? Use tiles at this one page website to discover the pattern of square numbers. See if you can solve the challenge. Once you have your solution you can check the solution given right at the website.
University of Cambridge
University of Cambridge: Nrich: All in the Mind
You will have to use visualization to help you solve this challenge. At this one page website, you will be able to check your solution.
University of Cambridge
University of Cambridge: Nrich: Dicey
If you can visualize a cube and turn it around in your mind, then this is the challenge for you. This one page website has the solution available to check your thinking.