Variables:
a) child - age, cognitive ability, gender, social experience, & psychological needs
b) family - economics, affecting what media are purchased (videos, books, CDs, games, apps, MP3s); time (alternative leisure activities pursued - games, sports, museums, trips); mediation (amount of supervision with media exposure)
c) bidirectional - what the child brings to media that effects change (computer knowledge); how media changes the child (surfing the internet provide various experiences)