Early English Language Learning (and check out related videos)
Grade One English Vocab for Android (or other phonics or vocabulary apps)

For Teachers:
Google Apps

Free Software:

Picasa photo organizing
OpenOffice is like MS-Office
CutePDF pdf (Acrobat) writer
GIMP is like Photoshop
IrfanView image viewer
Google Earth interactive globe
ZoomIt for drawing on the screen

Firefox web browser
Chrome web browser
Skype internet phone
Comic Reader

VLC video/music player
iTunes for music libraries and podcasts
YamiPod an iTunes alternatve for iPod management.
Miro for video podcasts and RSS etc
MovieMaker 2 video editing
PhotoStory for making slideshows easily
Audacity audio recording/editing

CD BurnerXP for burning CDs, DVDs, etc.
Microsoft Security Essentials antivirus, antispyware
Avast antivirus
Spybot S&D antispyware
Ad-Aware antispyware
uTorrent for downloading bittorrents
7-zip file archiving/unarchiving
TightVNC remote admin
XP PowerToys
ObjectDock OSX-like dock for Windows
Ubuntu Linux