The Happy School Days Demo displays a Primary Sidebar to the right of the content area. To configure the primary sidebar go to Dashboard > Appearance > Widgets > Primary Sidebar > drag your desired widgets into this location.
The Primary Sidebar in the demo displays the following widgets:
Genesis User Profile
Genesis eNews Extended
Genesis - Featured Posts
Text Widget (displaying advertising message)
(Click on the image to make it larger to view the settings)
Be sure to click the Save button to preserve your settings.