lwty.org is described as 'worksheets or practice exercises, calculators & answer sheets to engage the grade school students to learn, practice, test & verify the answers themselves to measure the progress of their own' and is a Calculator in the Education & Reference category. There are more than 50 alternatives to lwty.org, not only websites but also apps for a variety of platforms, including Android, Windows, Mac and iPhone. The best alternative is SpeedCrunch, which is both free and Open Source. Other great sites and apps similar to lwty.org are Qalculate! (Free, Open Source), Windows Calculator (Free, Open Source), Numi (Freemium) and Soulver (Paid).
A kickass, open-source calculator that lets you do calculations and unit conversions naturally, with features like: - weight conversion - length conversion - temperature conversion - currency conversion Super simple to use. Caligator works the way you think.
SpeQ is a small, extensive mathematics program with a simple, intuitive interface. All calculations are entered in a sheet. In there you can freely add, edit and execute calculations. SpeQ supports all common functions, constants, and units.
Programmable scientific calculator which has more than 150 mathematical functions and all of them return as many digits as you need. It can calculate with real numbers, complex numbers, fractions, vectors, matrices. Commands if, goto and print can be used to create scripts.
Rule of 3 Calculator is a portable tool that allows you to apply the mathematical Rule of Three in an easier, faster and more practical way! In order to represent decimal numbers, you must use "." instead "," (Example: 1.5 _ 2.33 _ 5.34687)