在线工具

Explore curated, beautifully designed presentation decks, slides, keynotes, and guidelines, all chosen for their exceptional design quality.

Discover Mathigon, the Mathematical Playground. Learning mathematics has never been so interactive and fun!

Explanatory solutions, answers and hints for your math textbook exercises. Try our own eCourses developed with care to maximize your grades start using it today for free!

The future of online learning

A massive, collaborative map of the urban harvest uniting the efforts of foragers, freegans, and foresters around the world. Explore and share information about the sources of free food in your neighborhood.

TimeGuessr - the game that tests both your geography and history knowledge. Guess the right time and location of a historical photo.

Mathwords home page

Free tutorials cover AP statistics, probability, survey sampling, regression, ANOVA, and matrix algebra. Written and video lessons. Online calculators.

CellMapper is a crowd-sourced cellular tower and coverage mapping service.

Find helpful math lessons, games, calculators, and more. Get math help in algebra, geometry, trig, calculus, or something else. Plus sports, money, and weather math lessons, too.

Write an awesome description for your new site here. You can edit this line in _config.yml. It will appear in your document head meta (for Google search results) and in your feed.xml site description.

Fourier transforms are a tool used in a whole bunch of different things. This is a explanation of what a Fourier transform does, and some different ways it can be useful.

MusicStaff.com is a free directory of over 10,000 music teachers worldwide. Use our powerful search tools to find the right teacher nearby.

Learn about synthesizers via Ableton’s interactive website. Play with a synth in your browser and learn to use the various parts of a synth to make your own sounds.

Maps and database of 802.11 wireless networks, with statistics, submitted by wardrivers, netstumblers, and net huggers.

Welcome to my math notes site. Contained in this site are the notes (free and downloadable) that I use to teach Algebra, Calculus (I, II and III) as well as Differential Equations at Lamar University. The notes contain the usual topics that are taught in those courses as well as a few extra topics that I decided to include just because I wanted to. There are also a set of practice problems, with full solutions, to all of the classes except Differential Equations. In addition there is also a selection of cheat sheets available for download.

AI灵感PPT是一款智能PPT生成工具，提供PPT生成、文章总结PPT功能;支持AI配图、AI配音和AI创作,快速制作自动演讲的PPT；工具内提供海量PPT模板,能够在线自由设计PPT,使我们很轻松的就能做出非常漂亮的PPT设计。

visaindex.com is a one-stop portal for all information related to passport ranking and visa-free travel opportunities.

Puzzles from Quant Interviews

IXL offers online maths practice covering preschool through year 12 maths and everything in between. Students will enjoy learning with IXL's fun and interactive questions, including graphing, drag-and-drop, select-and-edit and more.

Collection of math exercises and math problems. Primary school, high school and college math problems and math exercises with correct answers.

An encyclopedic collection of math resources for all grades. Arithmetic games, problems, puzzles, and articles

Online topographic (topo) maps with trails and high-resolution aerial photos of all the United States (US) (USA) and Canada. Topography of the USA.