An
introduction to

Secondary
Mathematics
A subsection of Math

This page is one small part of Good Sites for Kids!

*“Let's face it; by and large math
is not easy, but that's what makes it so rewarding when you conquer a problem,
and reach new heights of understanding.” - Danica
McKellar*

21 GIFs That Explain Mathematical Concepts from IFLS. For secondary students ages 14-15 and up, and their teachers. From radians to logarithms, from Pi to sines, and more. "As we usher in the start of a new school year, it’s time to hit the ground running in your classes! Math can be pretty tough, but since it is the language in which scientists interpret the Universe, there’s really no getting around learning it. Check out these gifs that will help you visualize some tricky aspects of math, so you can dominate your exams this year." Useful!

100,000
Digits of Pi Just in case you ever wanted to know, here are the first
100,000 digits of pi, on one page.

Pi is the ratio of a circle’s circumference to its diameter.

"Circumference is the distance around the edge of a circle. It is a type
of perimeter."

"Diameter is a straight line going through the center of a circle connecting
two points on the circumference."

Credit for the quotes and the graphic = MathIsFun

Pi expressed as a Base 10 digital number = 3.14159...> infinity.

Learners who move on past algebra and geometry can leave the digits behind,

and start using radians as they start trigonometry.

AAA Math New and improved with even more topics! An oldie but still growing and going. Many teachers think this is one of the best math sites for online learning. Covers K-8 Common Core math content requirements, always has. Generally, a short tutorial is followed by practice activities - open or times at the teacher's choice. Available on CD, too! Now with sections for Geography (US States, Countries), Spelling, Vocabulary,(both at AAASpell) and Sudoku! Este sitio también está disponible en Espanol - Clique aqui.

After School Mathematics "The After School Math website is a full-featured math website for grades 5-8 created by after school staff and credentialed teachers. The site consists of 10 thematic activity modules, each with at least four activities. These content standard aligned activities are fun, hands-on, and provide opportunities for small group interaction, cooperation, and student leadership." Go for it!

Algebra (Point plotting and line graphing) from FunBased Learning. "Need to learn how to graph points? Here's a free, fun, interactive game by a former Math teacher that teaches you how. Play it online right now for free." Graph Mole (three levels) and Line Gem 1 are engaging and get the job done.

Algebra: Southwestern Middle School's Thinking Maps "A resource for teachers, students, parents, and other creative minds" Eight "Thinking Maps" take learners step by step through some of the basic knowledge and skills. Among these are: Translating Verbal Phrases into Algebraic Expressions and Solving Proportions (Similar Figures). We put the links in so you can explore this technique. As you see, it walks learners through the process of problem solving. Scaffolding works with reading and writing, now it works with arithmetic as well :) Southwestern Middle School is in DeLand, Florida. Click "About" for the email address of the lady in charge of these maps. She welcomes additions to the Thinking Map collection.

All About Measurement Part of AAA Math The name says it all! Time, temperature, distance, more.

Avro's Adventure is a great ThinkQuest site about graphing distance, rate, and time. Covers D=RT, slope, vectors, position, acceleration, velocity, and how they all interact. Thirteen different lessons explain it all very well.

A Billion Degrees of Separation "We take the temperature of the universe from absolute cold to 'absolute hot'. " 883 X 4000 graphic goes from - 273.15C to 1.417x1032C (aka the Planck Temperature). Subdivided into Elements, Living Things, Man-Made, Earth, Solar System, and Universe. So if you need to know the boiling point of iron, the temperature range where tardigrades can live, the melting point of butter, the temperature of lava, the surface of Mercury at night, or the surface temperature of Sirius; they are all on this chart. A BBC project via ScienceAlert.

BrainCake Welcome to the Girls' Math & Science Partnership, a program of Carnegie Science Center. Based in Pittsburgh, "BrainCake is an online sisterhood for girls 11 – 17 and stakeholders focused on girls’ inclusion in the areas of math, science, technology, and engineering. BrainCake.org features forums, programs, scholarships, virtual mentoring, girl blogs, podcasts, homework help, research and resources in a framework that integrates pop culture, science, and learning."

ChiliMath
teaches the concepts of algebra. "At this time, the
website covers introductory, intermediate, and advanced algebra topics/lessons
along with video tutorials, practice exercises, and handwritten worked
examples. I also offer free math tutoring to help students with their
homework." *Introductory Algebra*
has seven lessons covering the things students need to know to start out
with a good foundation. *Intermediate Algebra* has 29
lessons covering exponents, factoring, linear equations, polynomials,
quadratic equations, slopes, and more. *Advanced Algebra*
covers 39 topics: complex equations, Cramer's rule, determinants,
functions, inequalities, lines, logarithms, matrix operations, quadratic
equations, radical equations/expressions/inequalities, and systems of
linear equations. AND he offers free
tutoring by email! So we tried this out and it was wonderful, even right-brainers
could handle this - the step by step teaching of the processes is very
well done - better than most hard copy textbooks out there. Kudos to Michael
Estela, who emailed GSFK about his site!

Comparison of Recent and Historic Earthquakes by Energy Release From the US NWS Pacific Tsunami Warning Center, this Youtube animated graphic compares the sizes of quakes using expanding, overlaid circles. Quakes range from the 5.8 in Virginia 2011 to a 9.5 monster in Chile, 1960. It's really easy to see the changes as the Richter Scale number increases. A 1.0 point change makes a big difference, and even a 0.1 change is noticeable. BTW the U.S. Geological Survey (USGS) does not use the Richter Scale anymore. It's been replaced by the moment magnitude scale, which is more accurate.

Coolmath Algebra 1 and Coolmath Algebra 2 pretty much cover all of high school algebra, from exponents to permutations, and everything else along the way. Nice and slow explanations of each topic. Topics build upon one another, too. Periodic exercises to check understanding. FREE, all students have to do is the work.

Create a Graph from NCES KidsZone. Kids can create five types of graphs, input data, and print it out. Includes a tutorial.

International Space Station - Current position of the ISS "Where is the International Space Station right now?" You can find that out with this site! It always shows "What the astronauts see right now.", which is a straight down view onto a Google Earth surface. "Ground track" shows the ISS' position on a map of the world. Both displays are always on, and are updated by the second. UTC time, latitude and longitude, speed, and altitude are all shown. Choose between miles and kilometers. What a wonderful data source for mathematics story/word problems, geography projects, and astronomy.

Dimensions "A walk through mathematics! A film for a wide audience! Nine chapters, two hours of maths, that take you gradually up to the fourth dimension. Mathematical vertigo guaranteed! Background information on every chapter: see "Details". Free download, and you can watch the films online! The film can also be ordered as a DVD. This film is being distributed under a Creative Commons license."

Edu Gain "Learn Smart" Here's an international site (free registration) that emphasizes mathematics. Their essay on opening children's minds to mathematics is a good read on its own. The site has two sections; Math Olympiad (Higher Order Thinking Questions), and General Math (online and printables drills). Not a site for slackers, kids will have to work and think here. Thanks, Anamika Sinha, for the email about Edu Gain!

Egyptian Mathematics Numbers Hieroglyphs and Math problems for kids Part of Discovering Ancient Egypt. This page covers numerals, counting, and fractions. (Everything is Base 10 - decimal.) They are word problems that will make kids use multiplication and division. There are some algebra problems for secondary students. Fascinating stuff.

The
Feynman Lectures on Physics, The Most Popular Physics Book Ever Written,
Now Completely Online "... arguably the most popular physics book ever
written, selling more than 1.5 million copies in English, and getting translated
into a dozen languages." Link goes to Open Culture so you can roam around
their vast treasure trove of educational resources - and we mean* vast!*
The actual lectures are hosted here,
by CalTech. Anyone who truly wants to may read all the physics they can hold
here. Reading these online is free but legally
getting hard copies costs money. Around US$130 give or take. (We really need
to do up a Physics site, a Chemistry site, etc, etc, etc.)

Fraction to Decimal and Millimeter Table from HamUniverse "Convert fractions to decimals and millimeters and reverse." Nice! It comes with good, clear instructions. It is handy if you don't want to use a calculator and have to keep rounding up or down and maybe make a mistake. Use this table, it works.

Free Mathematics Books 258 math books available online for reading or downloading. We're talking high school to university-level mathematics here. "Here is an alphabetical list of online mathematics books, textbooks, monographs, lecture notes, and other mathematics related documents freely available on the web. I tried to select only the works in book formats, "real" books that are mainly in PDF format...The list is updated almost on a daily basis.."

GNUmber Munchers "is an educational math program based on MECC's early 80s munchers games, with new graphics." So writes Will Heublein, whose two fun and playable Number Munchers tributes are your freeware alternative to hunting down those old games and trying (usually without success) to make them run again. OK, so these are not exact clones of the MECC games, but they're close enough! We've been using them with elementary and middle school students for a few years now and they get the job done. No mouse needed, just use the arrow keys. GNUmber Munchers 2010 is an online beta version that runs fine on Internet Explorer. We wish more people would emulate Mr. Heublein and redo some of the good old MECC games! To download these games: Go to the very bottom of the GNUmber Munchers page where it says "Old Windows versions (Downloadable .exe files):" Standard version is for upper elementary/middle/jr high students, Elementary version is for elementary kids. What is GNU?

Geometry Teaching Ideas This Pinterest page by Russell Mullins has 500+ pins of teacher helps, ideas, and lesson plans. A wonderful potpourri of things for teachers.

*What
Is Gerrymandering? A short video explains what's wrong with this ugly
political practice. Watching it gives learners the needed background to appreciate
the importance of fighting gerrymandering with geometry!*

Meet
the Math Professor Who’s Fighting Gerrymandering With Geometry

This link's from A Mighty Girl's Facebook site. The
original article from The Chronicle

of Higher Education explains it in a more academic manner. Basically, Professor
Moon Duchin

of Tufts University, "has helped create a program to train mathematicians
to serve as expert

witnesses in court cases over redrawn electoral districts." Since courts
all the way up to

the US Supreme Court, have problems understanding gerrymandering, this is
a good plan to

overcome this evil practice. Read one or both articles, and learn.

Graph 4.3 Here's a powerful upper grades' free function graphing program from Denmark (it's in English). Draw functions, draw relations, save as graphics and .pdf, evaluate, calculate, point series, trendlines, shade, label, create your own custom functions. Another SourceForge project. Made by Ivan Johansen. "The program is open source (GNU GPL) and you may give it to whomever you like."

Graph Sketcher from Interactivate. Students input equations and see what results on this interactive X Y coordinate chart. Discover slope form, y-intercepts, parabolas, anything that would work on graph paper works here.

Hooda Math Games section, divided into Geometry, Arithmetic, and Logic. Two or three pages of games in each category. It's refreshing to find Logic games online! A well regarded site with good math games.

HOT
X: Algebra Exposed!
Danica McKellar is back! This time she explains *algebra* to girls.
Is she qualified? Here's her chops: "Best known for her roles on
The Wonder Years and The West Wing, Danica McKellar is also a three-time
New York Times bestselling author, internationally-recognized mathematician
and advocate for math education. A summa cum laude graduate of UCLA with
a degree in Mathematics, Danica has been honored in Britain's esteemed
Journal of Physics and the New York Times for her work in mathematics,
most notably for her role as co-author of a ground-breaking mathematical
physics theorem which bears her name (The Chayes-McKellar-Winn Theorem)."
So yeah, she's qualified. What we like about this book, and all her math
books for tween and teen girls is - she's been there & done that -
she explains things in a special girl-to-girl BFF way, *without*
dumbing down the math. Teen girls and co-eds use this book and it really
helps!

inch/mm Conversion Chart from Maryland Metrics. Handy chart compares inch fractions and decimals with their metric equivalents. The site also explains how to convert, and features a fast interactive conversion calculator. This is from an industrial supply firm in Maryland, where people use these tables in a real life business environment.

Informal Geometry by MathMastery Inc. Video clips and interactive, downloadable Flash videos cover Geometry in 13 progressive units from intro to perimeters up through volume. Also covers using a compass and a protractor. Elementary kids who know their times tables could use this easily. Another fine example of what you can find at Curriki!

Interactive Math Simulations from PhET at CU Boulder. Here are 28 mathematics-related playable simulations - everything from fractions and times tables to physics, upper level math, and playing Plinko! Play online (needs Java), or download and install them, or embed them in your webpage! Don't forget to see the rest of PhET's simulations!

Interactivate has 133 Java-based math Activities. You can browse by audience, subject, topic, or resource type. "Browse by audience" gets you a choice of Grades 3-5, 6-8, 9-12, and college. The Discussion page has dialogues between a teacher and a student for 117 math topics! Each of these could be easily converted into a ready to go math lesson! The Lessons section has 90 ready to go NCTM lesson plans for print outs. The Tools section contains 44 of the activities pulled out of the Activities section. The Dictionary is a good, basic glossary of 188 math terms. The Textbooks sections is a MAJOR asset. Here, you can match ("Align") activities to chapters and lessons from textbooks from these series: Connected Math, Math Thematics, Mathematics in Context, and MathScape! Example: From MathScape Book 1, "What Does the Data Say?", Lesson 2, Name Exchange: You get two Interactivate Activities called Box Plot and Box Plot 2. The Standards section has NCTM math standards for grades 3-5, 6-8, and 9-12. This was a Kim Komando Cool Site of the Day. Note: This program requires Java.

Jefferson Lab science education This center for the study of subatomic particles has a very strong education outreach program!

There is a substantial Teacher Resources section:

There is a Games and Puzzles zone (Javascript required):

Just Math Tutorials YouTube videos of every middle school, high school, and many college math topics. This guy explains it all. Talk about a labor of love! Algebra, trigonometry, calculus- from scientific notation and how to add exponents to linear equations, limit problems, differential equations, statistics, SAT practice; subdivided into dozens and dozens of videos. Perhaps in the spirit of Khan Academy but only covers maths. reddit.

Khan
Academy "is a not-for-profit 501(c)(3) with the
mission of providing a world-class education to anyone, anywhere...We
are complementing Salman (Khan's) ever-growing library with user-paced
exercises--developed as an open source project--allowing the Khan Academy
to become the free classroom for the World." 1800+ videos cover math
from 1 + 1 up through differential equations; Science: Biology, Chemistry,
Physics, Organic Chem, Cosmology, Astronomy; History; Finance (BIG section!);
Test Prep: SAT, GMAT, CAHSEE, IIT JEE. The videos are wonderful! This
is amazing and FREE! (Oh, all right then! * KHAAAAAAAAN*!!)

KS3 Bitesize Maths For upper elementary through middle school/junior high in American parlance. Excellent, large group of well organized activities reviews and tests cover practically the entire math curriculum! Not cute and flashy like the KS1, but students can find anything they need to review in here. Presumes self-discipline or an attentive teacher, of course. Thank the BBC, who obviously put a lot of effort into this magnum opus.

Math Calculators! Here are 30 math calculators, each one calculates something different. bottom. Some are funny, others for serious work, all are accurate. Kitchen measurements, dog years, wind chill, map scales, planting, prime numbers, energy terms, weather, money, savings, time zones, binary, more, more, more!

Math Grades 7-12 Middle and High School Math ideas. "If you follow this board I will invite you to pin to it! Let's fill this board with Math resources for older kids!" This Pinterest board is packed with ideas, graphics, lessons, and coverage of most if not all 7 - 12 mathematics subjects.

Math Open Reference "Mission: A free interactive math textbook on the web. Initially covering high-school geometry...Using interactive tools and compelling animations, it provides an engaging way to learn and explore the subject. Teachers will have new ways to teach, and the students a new way to learn that is fun and engaging." Anything you need to learn about high school geometry - plane, coordinate, or solid - it's in here! One example: Circles. Interactive with Java animations. Graphical functions explorers, too. This is absolutely amazing! Hard to believe it's free.

Mathtutor "To bridge the gap from school to university study, to revise or find the maths topic you missed, you will want to meet mathtutor. Video tutorials, with diagnostics, summary text and exercises, take you through more than eighty topics in the way you choose." ("revise" = "study for an exam") This site is designed to help secondary school/high school students to brush up on concepts they need to learn to (1) graduate, (2) learn for a job, (3) study for college entrance exams, (4) prepare for college mathematics courses. The seven "subject areas" cover the spectrum from basic fractions up through differential and integral calculus. "Clicking a title from the left hand 7 subjects will open up a list of topics, each one having a video tutorial, support text, diagnostic test and an exercise to do." It's free, there are diagnostic tests, the videos are very good, and you work at your own pace!

Math Warehouse for secondary students, is kind of like a jungle of mathematical awesomeness! The further you go in (figuratively speaking) the more amazing interactive examples, exotic online problem-solving calculators, online games, lessons, and demos you find! Covers everything from angles to vectors, including algebra, geometry, trigonometry, and the formulae for all of it! Also covers scientific notation and the FOIL method of multiplying binomials. Grab points of a polygon and watch angles and lengths change! See a calculator show what your polygon looks like. When a calculator solves a problem it shows the work. It's like opening a treasure chest!

Math Worksheets Land "We now have over 4,000 PDF files that total over 12,000 printable pages. 100% free as always! Funny thing, I'm no where near done." At least a page on each of 40 math topics - everything from Kindergarten Math to Logarithms, Linear Equations, Polynomials, Scientific Notation... Also indexed by grade level. Aligned to the Common Core standards. FREE pdf files to download/print! Thanks for the emails from "Julia, Retired Middle School Math Teacher, Mom of 3, Grandma of 4, and Tired"

Mathematics - Miss Deely's Website from the UK was recommended to us on FB. That was fortuitous, because this is a fine site for maths! It covers everything from the multiplication facts (times tables) up through trigonometry and advance algebra. The way the material's presented is what makes the site so useful. She has six level's worth* of in-class lecture notes, discussion slides of worked problems, homework assignments and solutions, advice and encouragement. This is a place both students and teachers need to see! *Level 2 (1V), Level 2 (2Y), Level 3 (2T), Level 3 & 4 (3.24), National 5 (4.21), and Int 2 (5.25)

Maths for all!!! Covers Algebra 1 and 2, Geometry, pre-Calculus, Trigonometry, and Statistics. Designed for grades 5 - 8. Dozens of concepts explained, with practice exercises to try for each one. Some of these are: percentages, fractions, volume, equations, inequalities, linear equations, variables, shapes, graphs & charts, logarithms, matrices, and factorials. "Problems, explanations, and solutions." Revise means to study, to review for a test. Great site from the UK.

Mathwords: "Terms and Formulas from Beginning Algebra to Calculus. An interactive math dictionary with enough math words, math terms, math formulas, pictures, diagrams, tables, and examples to satisfy your inner math geek." Indexed both by beginning letter and by subject area. Also covers fractions and geometry. A great reference and teaching aid!

Mayan
Numbers "Mayan Number Symbols. Great for Gifted kids learning why
we

use base 10 and other cultures have used different bases." - Sara Patrick
Strait.

The Maya number system was a base twenty system. Explore and enjoy!

Metric Conversion & Metric System Easy and concise, this site does interactive metric to US conversions for: length, weight (mass), temperature, area, volume/capacity, mileage, enegy, force, and power! There are also tables giving equivalent volume, area, mass, and length values. There are explanations of weight vs. mass, and how to do temperature conversions. Excellent reference and help site!

Metric Conversions Nice! Easily switch between metric and American measurements! Students would find this useful for checking answers after they work them out :P (Better be able to show your work.) They also have mobile apps, conversion tables, and an online calculator!

Mission Magnetite from Cyberchase Games Central! In this 3-way matchup, you must match a percentage with its equivalent fraction and graphic, in five increasingly more challenging levels! Good learning for kids and a good refresher for adults!

Mudd
Math Fun Facts Who says math is dry? This middle school + site's
fun math facts really *are* fun.

National
Library of Virtual Manipulatives *Interactive online manipulatives*
for preschool through high school! Broken out by grade level and subject matrix.
This is a great site!

Number Games from Kids Math Games. Explore fractions, decimals, percentages, probabilities, multiplication, division, quizzes, worksheets, even an addition game!

PhET Simulations - HTML5 PhET has six new simulations (more coming) that use HTML5 instead of Flash or Java. This means they are compatible with any modern browser, AND with tablets!* You don't have to download anything anymore. See the 2:26 video, it's worth watching. (*This is kind of a big deal.)

Plotting Points on a Coordinate System from the University of Wisconsin Online. Fast and accurate introduction to the subject. Animated Flash slides walk students through the basic x y and ordered pairs concepts, then lets students test their knowledge with interactive plots. This is one of very many subjects covered in their Flash-powered Learning Objects, a huge collection of modules arranged by subject.

Pythagoras Theorem (called Pythagorean Theorem in the US) This site explains everything about the Theorem. It includes a video and links to more information. A good resource. Thanks to Darren Cross.

Quizzes.cc - Online Quizzes, Tests, Trivia, Worksheets, and Free Games "... provides math quizzes for teachers and students. You can create a quiz and select the range of numbers you'd like to use. Students can grade the quiz online and generate new problems for more practice." Quizzes for all four elementary operations, plus times table quizzes and a nice metric conversion chart. There are also children's literature, science, and geography quizzes. Secondary students can practice metric conversions, some middle school science, and world geography. Thanks to John @ Quizzes.cc for the email!

Radian (this link goes Wikipedia) 360° was made up by the Babylonians. All the measurements of angles in degrees come from them, too. Degree measurements are a fine tool for learning the basics of geometry and for everyday use. However, if you're a math geek, or would like to be (trigonometry, calculus, and so forth), or if you need to learn maths past algebra, you'd do well to learn the ways of radians. MathWithBadDrawings has a good explanation of how radians work. For those who want a video, Khan Academy has a good series. MathIsFun has a good and simple explanation that's easy to follow.

An arc of a circle with the same length as the radius of that circle corresponds to an angle of 1 radian. A full circle corresponds to an angle of 2p radians.

Slope Formula Style (music video) 8th Grade students and staff sing about the slope formula, Gangnam Style. Inspirational learning reinforcer.

Slope Music Video Y-intercept formula dubstep. Accurate and fun.

Sampler of Mathematics for gr9-10/ 14-16yr From Curriki. "The curriculum resources contained in this folder represent a selection of high-quality materials from the Curriki repository for grades 9-10/ages 14-16 in Mathematics." There are some interactive online actitivities in here in zip file form for you to unzip; also some .pdf lesson plans and online lesson plans.

Smart Kit School-Safe Puzzle Games "stimulate thinkng, logic, and problem solving." Here are oodles of thinking games in several categories. All have music and live action, and no violence. Make sure you understand what you are supposed to do before playing, instructions are at the bottom of each games's start page. Useful to teachers. Have fun! Thanks to Ryan at Smart-Kit for the email.

This 4:39 Youtube video from TED-ed shows some different
ways to arrange

(sort) books on your bookshelf. All the sorting algoritms are demonstrated
and

explained. In Secondary Math.

That Quiz Click this link now!! Scalable, customizable quizzes in all levels of K-12 mathematics. Geography, languages, cell structure, elements, periodic tables, anatomy, conversions. Their righteous pitch: "What is ThatQuiz?

Registration is free and teachers who register receive complete record-keeping of student grades. They have access to more precise test-generation tools, can create single tests with questions from different categories, can create matching and multiple choice questions, and can access a public test library. There is no reason for students to register, since the additional features are only useful for teachers."

Trigonometry Pile Up! "This resource is a challenging puzzle to consolidate learning on trigonometry. The idea is that pupils have to start with the information they have in the bottom triangle and work their way up through the stack, finding missing side lengths to allow them to calculate the length of the hypotenuse of the top triangle. The puzzle can be solved with trigonometry alone (finding missing sides and missing angles) or Pythagoras’ Theorem can be used at some points as well. This puzzle can also be used to clearly demonstrate why you shouldn’t round numbers mid-way through a calculation." You can download the puzzle from the site: "Click here to download the resource." gets you a BIG pdf pic of the puzzle. © 2012 greatmathsteachingideas.com

*Unit
Converter Express Version Lets you convert almost any unit of measure*

into another unit of measure. Everything from currency (BIG list-includes
Bitcoins),

common units (length, weight, mass, data, distance, speed, angle, force, time),

engineering (volume, torque, inertia, acceleration,velocity, density), Heat
Converters,

Light, Electricity, Magnetism, and Radiology Converters! Even lumber!
If you need to

convert a unit of measure, it's in here.

Virtual Nerd from Pearson "Real math help. Over 1,500 video lessons covering Middle Grades Math through Algebra 2." Over 2,600, now. Also, Geometry has been added. All are organized by topic.

Webmath is a math-help web site that generates answers to specific math questions and problems, as entered by a user, at any particular moment. The math answers are generated and displayed real-time, at the moment a web user types in their math problem and clicks "solve." In addition to the answers, Webmath also shows the student how to arrive at the answer. Covers Kindergarten up through calculus and financial mathematics.

Whatcom Community College Online Math Center Twenty-one links to free math courses, more links to resources, too. Algebra, calculus, fractals, more. Mostly this is for parents, teachers, and secondary students.

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