The Launch Pad stage introduces children to tennis through games and fun activities. Children learn the basics of tennis including how to rally. There are a number of program options at this stage, including the official Launch Pad program Wilson PeeWee tennis.
Court size: variable 
Tennis ball: red ball (25% compression)
Recommended racquet size: 19–23 inches

The Red stage is for beginners. The red ball is larger than a yellow ball and doesn’t bounce as high (just 25 per cent compression), making it a breeze for even the youngest players to hit it comfortably. The courts and nets used in the Red stage are much smaller and easier for kids to move around.
Court size: 3 m × 8.23 or 6 m × 10.97 m
Tennis ball: red ball (25 per cent compression)
Recommended racquet size: 21–23 inches

 

After mastering the Red stage, children move on to the Orange stage where the ball bounces a little higher (50 per cent compression) and the court is a bit bigger.
Court size: 6.4 m × 18.29 m
Tennis ball: orange ball (50 per cent compression)
Recommended racquet size: 23–25 inches

The ball used in the Green stage has a higher compression (75 per cent of a yellow tennis ball) and children play on a full-size court.
Court size: 10.97 m × 23.78 m (full court)
Tennis ball: green ball (75 per cent compression)
Recommended racquet size: 25–27 inches