inherited_test-ar.rb

require "active_record"
class Mother < ActiveRecord::Base
  def self.inherited(subclass)
    puts "Base Class: #{self}"
    puts "New subclass: #{subclass}"
  end
end

class Taro < Mother
end
# => Base Class: Mother
# => New subclass: Taro

Object.const_set :Jiro, Class.new(Mother)
# => Base Class: Mother
# => New subclass: #<Class:0x007fd8f3adb640>

inherited_test.rb

class GreatMother
  def self.inherited(subclass)
    puts "Base Class: #{self}"
    puts "New Subclass: #{subclass}"
    super
  end
end

class ChildTaro < GreatMother
end
# => Base Class: GreatMother
# => New Subclass: ChildTaro

Object.const_set :ChildJiro, Class.new(GreatMother)
# => Base Class: GreatMother
# => New Subclass: #<Class:0x007fd150834248>
p ChildJiro.superclass
# => GreatMother