A matching game for number facts, decimal and fraction conversions, and measurement conversions.
http://www.mathsframe.co.uk/cardgame.swf

Other resources by this author can be found at:
http://www.mathsframe.co.uk/free_resources.asp

Compete against a friend, the computer or someone from around the world in a tug of war. To win, you have to compare the size of fractions quickly and accurately. Great fun! Note that the game can take quite a while if the competitors are evenly matched!

http://www.arcademicskillbuilders.com/games/dirt-bike-comparing-fraction...

An exciting way to practice creating equivalent fractions. You compete against your mates, the computer or other fraction-maniacs around the world to find equivalent fractions quickly and accurately.

http://arcademicskillbuilders.com/games/dirt-bike-proportions/dirt-bike-...

Ratio Stadium
Ratio Stadium is an additive arcade game in which the players have to find ratios that are equivalent to each other - and do it fast and accurately. Play against friends, against the computer or against other ratio addicts around the world. Addictive and great fun - three thumbs up!
http://arcademicskillbuilders.com/games/ratio-stadium/ratio-stadium.html

Ratio Blaster
Ratio Blaster is a one-person Space Invaders type game. How quickly can you blast the equivalent fractions out of the sky? Three thumbs up!
http://www.arcademicskillbuilders.com/games/ratio-blaster/ratio-blaster....

Two challenging puzzles.

Here is the blurb:
http://www.teacherled.com/2008/11/11/slide-puzzle-maths/

Here is the multiplication tables puzzle:
http://www.teacherled.com/resources/slidepuzzle/mslideload.html

And here is the equivalent fractions puzzle:
http://www.teacherled.com/2008/11/11/slide-puzzle-maths/

A fantastic interactive activity! Students get lots of practice at finding equivalent fractions, decimals and percents. Three thumbs up!

The website has a fact sheet, a worksheet, a quiz and (best of all) a game for teaching this activity.

The main website is at:
http://www.bbc.co.uk/skillswise/numbers/fractiondecimalpercentage/compar...

If you want to cut to the chase and just play the game, it can be found at:
http://www.bbc.co.uk/skillswise/numbers/fractiondecimalpercentage/compar...

A variety of great bingo games to reinforce fraction concepts - fraction to picture, fraction to equivalent picture, equivalent fractions, improper fractions, and fractions to decimals.

Three thumbs up!

Left-click to play on-line or right-click to download.
http://www.topmarks.co.uk/r.aspx?sid=3329

Equivalent fractions, simplifying fractions, improper fractions to mixed numbers.
For some reason, the simplifying fraction questions always simplify to a unit fraction.

Left-click to play on-line. Right-click (and Save Link As or equivalent) to download.

http://www.wmnet.org.uk/wmnet/custom/files_uploaded/uploaded_resources/8...

Click on the link below to download this flash activity, where students are asked to compare whole numbers, fractions or decimals. You can also create your own activities, including ordering measurements with different units.

http://www.topmarks.co.uk/r.aspx?sid=2452

Concentration Memory Game

You can choose to play the game to revise number facts, fraction concepts or fraction-decimal-percent conversions. Very nice implementation!

http://illuminations.nctm.org/ActivityDetail.aspx?ID=73