NEW YORK (Reuters) - MTV Networks' Nickelodeon will spend $100 million over the next two years to develop online games aimed at children as it seeks to tap a fast-growing part of the $30 billion industry.

The investment will pay for a slew of new subscription services, multiplayer games and virtual worlds for kids.

Eyed by many game developers as one of the fastest-growing segments of the business, so-called casual games are those such as puzzles or card games that can be played for just a few minutes or on the run.

Usually featuring simple graphics and controls, casual games have helped the industry expand its audience beyond the young male base that is more interested in games featuring graphic-laden gore and guns.

The division of media conglomerate Viacom Inc. said it will introduce several new online products in 2008 to 2009.

These include myNOGGIN, a subscription service of educational games for preschoolers and parents that will be offered with cable companies Charter Communications Inc., Cox Communications and Insight Communications.

The company also plans to launch the Nick Gaming Club, a subscription service featuring multiplayer games and three-dimensional avatars, or digital characters, that members can use to interact with other subscribers.

It is also expanding existing game services such as its AddictingGames Web site, which will debut a variety of casual virtual worlds, and its popular Neopets, which will be renamed as Neostudios and focus on developing online virtual worlds.

"Particularly in the kids' space, with more than 86% of kids 8 to 14 gaming online, we see great momentum for online casual gaming," Cyma Zarghami, Nickelodeon Kids and Family Group President, said in a statement.

Nickelodeon's online games strategy would compete with rivals Time Warner Inc.'s Cartoon Network and Walt Disney Co.DIS.N>, which also offer online games.