Everything you need to understand or teach Mother and Child by Joan D. Vinge.
The most obvious theme in Mother and Child is the dangers of unlimited technology. The plague which devastated the human civilization is almost certainly genetically engineered. The resulting decline in civilization and in technological understanding opens the door to the silicon-based "gods" and another theme in the book. The "gods" are outsiders manipulating the human societies for their own selfish purposes.
The parallel between the "gods" and the imperialistic governments of the past...