module ActiveAdmin::Resource::Scopes

def default_scope 

def default_scope
  @default_scope
end

def get_scope_by_id(id)

Returns a scope for this object by its identifier 
def get_scope_by_id(id)
  id = id.to_s
  scopes.find{|s| s.id == id }
end

def scope(*args, &block)

to your i18n files a key like "active_admin.scopes.scope_method".
If you want to internationalize the scope name, you can add
Create a new scope object for this resource. 
def scope(*args, &block)
  options = args.extract_options!
  title = args[0] rescue nil
  method = args[1] rescue nil
  scope = ActiveAdmin::Scope.new(title, method, options, &block)
  # Finds and replaces a scope by the same name if it already exists
  existing_scope_index = scopes.index{|existing_scope| existing_scope.id == scope.id }
  if existing_scope_index
    scopes.delete_at(existing_scope_index)
    scopes.insert(existing_scope_index, scope)
  else
    self.scopes << scope
  end
  @default_scope = scope if options[:default]
  scope
end

def scopes

Return an array of scopes for this resource 
def scopes
  @scopes ||= []
end