See: 
So, What's A Fraction?
 Fraction Computation Rules W/Examples

fract.xls  Movable fraction bars from 1/1 to 1/15 on multiple sheets.
 Why "Invert and Multiply" When Dividing FRACTIONS
 Borrowing to Subtact  Pictures to Justify the Computation

Multiple Strips & Fraction Bars
This page concretely presents multiples of a number and equivalent fractions.

strips.xls DIGITAL MANIPULATIVE on a spreadsheet with multiple strips & fraction bars.

The Decimal Bakery a math fairy tale on decimal computation

Fraction Computation Stated in Symbolic Form

A Game for Two Players  fun vocabulary drill on prime, composite, reciprocal, multiple

Recognition of Prime Numbers Game  a web page that permits one to test knowledge of the
primes and composites from 1 through 100

Divisibility Tests  2 through 10 with links to other resources

prime factorization of whole numbers from 1 to 122 in text form

Primes Spreadsheet  with a prime factorization of whole numbers from 1 to 122,
whole numbers from from 1 to 500 with primes marked in color

I'M PRIME
 primes, composites, divisibility, factor, lcm, gcf VOCABULARY
