This part of the Roblox experience — playing dress up — is, ironically, the most adult because it costs money. Avatar styling is an expensive hobby for a kid.

Amber Petersen was lounging in bed with her 7-year-old daughter last week, watching her play the popular children's video game Roblox on her iPad when she saw a disturbing display on the screen.

Roblox is an online platform and game creation system where users can design, share, and play games developed by other users. Launched in 2006 by David Baszucki and Erik Cassel, Roblox has gained ...

Kids who play Roblox games describe ‘scary’ virtual currencies and ‘cash grab’ random rewards.