There is no way to select activities in the Home views. However, there is a shortcut to change to the List view from Home view, but there is no way one can use the keyboard to select an activity and start it. Activities can be searched for but they can't be opened because of the above. (See http://bugs.sugarlabs.org/ticket/4660) Note that we are currently in Feature Freeze, therefore you should submit a patch, but not a Pull Request when you complete this task.