My daughter pressed a series of keys and now my desktop icons are WAY magnified?
It could be several things, first thing I'd check is System Preferences - Universal Access - Seeing tab - Zoom (set to off)
This page may be of help: http://support.apple.com/kb/HT3737
If that doesn't work, try right clicking (control + click) on an app icon, then press Show View Options. Then use the slider at the top to adjust the icon size. The standard size is 64x64.
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