Wikids - An encyclopedia that talks to your kids
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Litnerd - The Pixar for education, reading program for K-5 schools
Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
COOLPHABETS - Helping kids around the world learn their native alphabets.
Google Keep - Capture notes, share them with others, and access them from your computer, phone or tablet. Free with a Google account.