BrainPOP uses a great game titled Battleship Numberline (developed by Playpower Labs Inc.) to help students review concepts of whole numbers, fractions and decimals. They will practice determining where on a number-line specific whole numbers, fractions, or decimals should be. They will also estimate what whole number, fraction, or decimal an object is placed by on the number-line.
Disclaimer: This game is to review concepts by putting them to practical use. This game does not explicitly teach these concepts.