 This page is not the most organized. Please pardon the mess while I'm thinking!

GeometrySimilarity...GSRT
Dilates rectangle, nice intro to proportional sides and congruent angles
http://threeacts.mrmeyer.com/shrinkingdollar/ Activities and Explorations w/ Sketchpad or Geogebra  Proving similarity through dilations
http://connectsemass.org/documents/CollegeReadiness2013/E/E1.pdf http://www.geogebratube.org/student/m46619 http://quadrivium.info/GGB/SimTri.html Mathematics Vision Project (Secondary Mathematics  Module 6) http://www.mathematicsvisionproject.org/secondary2mathematics.html Helping kids understand the geometric mean:
http://www.cimt.plymouth.ac.uk/journal/kalder.pdf_ youtube animation for geometric mean: http://www.youtube.com/watch?v=Kvu_RVp0ZJY Possible Assessment or Group Exploration
http://www.illustrativemathematics.org/illustrations/603 http://www.illustrativemathematics.org/illustrations/1422 ...Right Triangles and TrigonometryGSRT
Introduction to the Pythagorean Theorem
http://www.yummymath.com/2012/watsonsave/ This activity was great! Video was interesting...at first kids didn't see that Pythagorean theorem should be used to create two triangles. I deleted the width of the field from the worksheet and we googled to find out. Also, I deleted the text at the top that said Bailey ran about 100 yards because some kids used that as their estimate. The thing that surprised me most was how annoyed the kids were because they couldn't get the "real answer". I told them it was whatever they figured out with their assumptions and estimates. "But couldn't someone go on the field and measure?" a student asked. I explained that the only way to determine the exact locations of the players were from the picture...that's all we had to go on. Nice activity and i would do it again. Activities and Explorations
Parallogram properities
Explore parallelogram properties using sketchpad. Open on iPad. http://www.geom.uiuc.edu/~dwiggins/conj22.html Possible Assessments or Group Explorations
Area of Polygons  using TrigRead more about this lesson on my blog  Teaching the Unit, not the Chapter
Triangle CentersCaution when applying to real world tasks
http://jwilson.coe.uga.edu/CntrTriLrngTsk/CenTriLrngTsks.html 
Algebra IWriting Variable Expressions
http://blog.mrmeyer.com/2014/makeovercentralparkthesetragicwriteanexpressionproblems/commentpage1/ Writing Variable Expressions: Link for teacher to create class https://teacher.desmos.com/centralpark# Teaching Linear Inequalities
https://vimeo.com/album/1983986 Worked wonderfully...kids were super excited. We plotted on large first quadrant grids. Then I extended the lesson by bringing in supermarket advertisements and having kids choose two products, then find out how many they could buy for a given amount of money. Segued fairly nicely into systems of linear inequalities as I told kids they could buy "no more than" a certain number of product, etc. Domain and Range
Desmos Online Graphing Calculator
Use to "show" rather than "tell" Click here for my own lessons on Domain and Range Examples of real world mistakes in math
http://www.huffingtonpost.com/2013/06/18/workmathfails_n_3442834.html?utm_hp_ref=mostpopular Solving Systems of Equations
Puzzle for Solving Systems of Unknowns  Can create additional puzzles. http://nrich.maths.org/1053&part=note Why do we factor equations?
http://betterexplained.com/articles/understandingalgebrawhydowefactorequations/ Introducing Parabolas
How Parabolic Flight Works http://www.incredibleadventures.com/zeroghow.html Video of person on zerog flight https://www.youtube.com/watch?v=drdBKMOZmTc 

Math Activities
Lessons for Practical Money Skills  from VISA (includes buying a car, budgeting, etc.)
http://www.practicalmoneyskills.com/foreducators/lesson_plans/
http://www.practicalmoneyskills.com/foreducators/lesson_plans/
Counting embedded figures  prepares for geometry overlapping figures
http://illuminations.nctm.org/Lesson.aspx?id=978
http://illuminations.nctm.org/Lesson.aspx?id=978
Hidden Pictures  Prepares students for complicated figures in Geometry
Print out or use online
http://www.highlightskids.com/hiddenpictures
Print out or use online
http://www.highlightskids.com/hiddenpictures
Other Great Filing Cabinets or Resources
Assessment Ideas
Writing Quizzes for easy feedback  Ashli Wolfram Demonstrations Projects
Animated ways to explore. Step by step instructions for Students in Geometry using Sketchpad
http://faculty.kutztown.edu/schaeffe/GSP/GSP.html List of other Filing Cabinets
http://ispeakmath.org/mathteacherresources/ Videos about Space for all levels of math
from NASA http://www.nasa.gov/audience/foreducators/exploringmath/home/index.html Videos: 100 Greatest Discoveries
Theory of Relativity http://science.howstuffworks.com/28750100greatestdiscoveriesgeneralrelativityvideo.htm 
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