We’ve assembled an online set of tools for use by a teacher or tutor looking for high quality free resources, or by a student who needs a little math, physics, or chemistry homework help. The following resources have been selected by our editors as representing the best of what is offered freely on the Internet.
Free Online Scientific Calculator
The Online Scientific Calculator at EEWeb.com (an electrical engineering community) comes fully-featured and can be used in-browser or downloaded for Mac or Windows. Here’s a description from the developers:
eCalc – Online Scientific Calculator with integrated Unit Converter. It provides scientific functions, algebraic operating mode, linear equation solver, root equation solver, history of your calculations, decimal to fraction converter, complex number with polar format or rectangular format.
Free Online Graphing Calculators
There comes a point in one’s education when you enroll in that chemistry, algebra, trigonometry, or calculus class that requires an expensive graphing calculator. Well, maybe it doesn’t have to be expensive! There are plenty of free online calculators that can save you the cost of a TI-89 Titanium. Of course you can’t walk into the SAT with these, but for the sake of homework, they’ll do the job.
Meta-Calculator is a graphing, scientific, matrix, and statistical calculator by PainFreeHomework.com in English, Spanish, and Mandarin Chinese with a powerful array of functionality. According to the website, an app version is in development.
A second high-calibur option is the Desmos calculator. While it has the advantage over Meta-Calculator of displaying the graph and the equations table simultaneously (and nicely updating the graph as an equation is edited), it has two drawbacks: 1) it is only for graphing, and 2) if you’re using the mouse rather than the keyboard, it is not immediately apparently how to stop entering exponents after you’ve started. This problem doesn’t stand for typed entries. On the bright side, this led me down the intriguing path of seeing what y=2x^2^x^x^x^x looks like.
A neat feature of Desmos is that its graphs are savable, and creative mathnuts have been making art with it. Have you ever seen a graphing calculator graph a calculator?
The Periodic Table of Periodic Tables, Period.
Perhaps an interactive periodic table could help provide some answers for that chem homework. My favorite is Ptable by Michael Dayah. Ptable is colorful, clean, and full of nice functionality. Clicking on an element displays the relevant Wikipedia entry in an overlay without leaving the page. Mousing over an element displays a magnified version of its box and visually links it to its category, e.g. “alkali metals” or “transition metals.” Mousing over the categories at the top highlights all of the elements that belong to that category. Neatest of all, there is a temperature slider so you can see what state each element would be in at whatever degree Kelvin, Celsius, or Fahrenheit–and this is just the main tab. There are additional tabs for properties, orbitals, isotopes, and compounds.
A Glossary of Chemistry
Can’t remember what a ligand is? Me neither. Try out this glossary. It’s concise, and often more straightforward than a Wikipedia article.
A Lewis Dot Tool
For those in need of chemistry homework help, we’ve posted resources for Lewis Dot Diagrams (or Electron Structures) before. Here is a straightforward Java applet where you pick a compound from a dropdown menu to modify. The applet tells you if you do it right.
This converter will give you more equivalencies than you could ever possibly need to know.
A Hyper-Reference of Physics
Hyperphysics by C.R. Nave is a physics reference presented as a visual concept map of clickable topics covering everything from classical mechanics to optics to quantum mechanics.
Thanks for visiting our toolset, and we hope it has been of help. If you have a free online learning resource you feel we might like to feature or review, you may apprise us of this through the comments below or via our “Contact Us” tab.
[This post updated 3.18.2014 to include eCalc.]