Kids can practice place-value knowledge through many free online games. FunBrain, Toon University and Gamequarium (see Resources, below) all have place-value games. Kids can practice identifying which digits are in which places, writing larger numbers and recognizing the different places in numbers from the hundredths to the hundred thousands.
Upper-elementary kids can use place-value charts (see Resources) to play games. Students can pair up and take turns rolling the dice. After each roll, the student writes the number somewhere on her place-value chart, trying to make the largest number. After each place is filled, students read each other their numbers to see who won. For example, if a student rolls a "5," he has to decide whether to put that in his hundred millions place or whether to put it in the ten millions place, hoping he'll rolls a "6" later in the game. Advanced students can use three dice.
The reverse of the game in Section 2, "Roll It Small," encourages students to make the smallest number possible. As partners take turns rolling, they choose where to place the digits on their place-value charts (see Resources). So if a student rolls a 1, she should write it under the highest value possible. You can have students only use part of the chart to make the game simpler, or allow them to skip a turn (and thus write "0") once during the game to make it more difficult.
Upper-elementary students should make digit cards, using index cards and markers. They should write digits 0 through 9, one digit per card. They can then manipulate these cards to follow your instructions, such as make the smallest number possible, make the largest number possible, make a number with odd numbers in the hundreds and hundred-thousands places, make a number between 400 and 600 or whatever you so choose. You can also have students work in teams to see who can complete the task most quickly or come up with the most numbers.