Calkoo provides free online calculators for almost any purpose! Calkoo is perfect for anyone who needs to do a few quick calculations.
Numerous calculator applications are available here that let users make various calculations a lot easier than they normally are. A simple bond yield calculator or a fuel cost calculator application can save you the valuable time you would otherwise spend on lengthy manual calculations.
Ptable is an interactive Web 2.0 periodic table. It provides dynamic layouts, property trend visualization, orbitals, thousands of isotopes, and 5 writeup sources. The application uses no Flash or images, giving all the scalability and accessibility of a normal web page (it can be viewed on any kind of computer and device).
The layout, unless differently specified by the user, automatically switch to fit the width of the screen. Using the check boxes at the top of the page allows to dynamically switch between various configurations (simple, with names, with electron configuration, and inline inner transition metals).
In addition to Wikipedia descriptions in all languages, write-ups, photos, videos, and even podcasts are offered in the first tab's dropdown. Write-up windows can even be torn off or docked to the edges to allow simultaneous use of the table while reading.
Data is acquired from primary sources and curated libraries. Layout and presentation were reviewed by the world's foremost periodic table academic, Eric Scerri. Translations and non-English element names, however, should be considered no more reliable than Wikipedia.
Search (into the box at the top right) can be performed by name, symbol, or atomic number. Advanced searches work, for example, on the atomic weight, number of orbitals, etc.
Most browsers, tablets, and phones can store the site and its data for use offline. Firefox prompts you with a notification bar at the top while Chrome and Safari directly save it.
Full descriptions in 40 languages from Wikipedia.
Tux Paint is a free drawing program for children (3 to 12) that combines an easy-to-use interface, fun sound effects, and an encouraging cartoon mascot who guides children as they use the program. It is used in schools around the world as a computer literacy drawing activity.
The program runs on multiple platforms. It’s simple interface presents a number of useful drawing tools and at the same time relieve the user of the need to think about the technical details.
Sound and visual helps are available: fun sound effects are played when tools are selected and used and a cartoon mascot appears at the bottom to give tips, hints and information.
Parts of Tux Paint have currently been translated into almost 100 languages.
Stamps, starters and brushes are stored using popular open formats (PNG, SVG, Ogg Vorbis, etc.) allowing parents and teachers to create their own content for use at home or in the classroom - even using completely free tools.
The 'Tux Paint Config.' program allows parents, teachers, and school technicians to alter Tux Paint's behaviour using a simple, easy-to-use graphical interface.
Scratch is a programming language that makes it easy to create animations, interactive stories, animations, games, music, and art. The outcomes can be stored and shared on the web within the Scratch system.
It is not only an ideal tool for the creation of simple and attractive interactive and/or animated learning objects, but it also serves as a learning instrument for young people. By using Scratch learners learn not only to create and share Scratch outcomes but more importantly they learn mathematical, logical and computational ideas, while also learning to think creatively, reason systematically, and work collaboratively.
Scratch is at first sight a bit difficult to learn, but there is a (short and simple) manual that helps everyone getting started within minutes. It is not a full blown animation tool but it is a lot of fun and very rewarding to work with.
Scratch is developed by the Lifelong Kindergarten Group at the MIT Media Lab, with financial support from the National Science Foundation, Microsoft, Intel Foundation, MacArthur Foundation, Google, Iomega and MIT Media Lab research consortia.