• Algorithms
Titled the "Algorithms" page, this site provides thorough examples of all they types of algorithms within addition, subtraction, multiplication, and division. For example, within addition, the site explains the partial sums, the left-to-right, and the rename addends algorithms.

This applet uses base-ten blocks on a place-value chart. You can form any problem you wish through four digits. When the top blocks are dragged onto the red blocks, they disappear. Although you can begin in any column, the model forces a regrouping strategy. Good for the traditional algorithms.

• Base Blocks Subtraction
This applet uses base-ten blocks on a place-value chart. You can form any problem you wish through four digits. The subtraction model shows the bottom number in red instead of blue. When the top blocks are dragged onto the red blocks, they disappear. Although you can begin in any column, the model forces a regrouping strategy as well as a take-away model for subtraction. Good for the traditional algorithms.

• Customized computation activities
This site allows teachers or students to customize practice regarding computation with addition, subtraction, multiplication, and division. The custom pages can be completed online or could be printed out for students to complete with pencils. Allows the user to select "maximum" and "minimum" numbers to create the problems.

• Elementary computation activities
This site provides links to printable activities relating to all kinds of computation at the elementary level. The activities would be appropriate for second to fifth grade.

• Funschool.com
The Funschool website consists of mathematical games on number concepts and operations, fractions, decimals, percents, geometry, probability, patterns and equations.

• Geometric perspective
The purpose of this website is to assist the user in looking at addition, subtraction, multiplication and division of whole numbers from a geometric, "hands-on" perspective and an algorithmic perspective. The site uses explanations with manipulatives to demonstrate the different algorithms. The site is intended for teachers but also states that parents and students are welcome.

• Math Forum
A part of the Math Forum website that features numerous resources on the computation of whole numbers as well as alternate algorithms such as lattice multiplication.

• Rectangle Multiplication
The Rectangle Multiplication applet (National Library of Virtual Manipulatives) will model any rectangle up to 30 x 30. The rectangle is split into two parts rather than four, corresponding to the tens and ones digits in the multiplier. The result is nicely correlated to the standard algorithm.

• Scott Foresman eTools
The eTools software provides several applets, including one that will allow the creation of a rectangle up to 50 by 100 that can be filled in with base-ten blocks the same as would be done with physical blocks (Similar to Rectangle Multiplication).

• SMILES
This site, sponsored by the School Mathematics Science and Mathematics Initiative for learning enhancement (SMILES), provides mathematics lessons that are divided into the following categories: Geometry and Measurement, Patterns and Logic, Probability and Statistics, Recreational and Creative Math, Practical and Applied Math, Arithmetic, Graphs and Visuals, Algebra and Trigonometry.