In late November Carmen Gómez Benítez, from EOI Valencia, published this presentation on Subject and object questions on her blog Mcargobe's Blog-Room.
It is a good opportunity for Básico 1 and Básico 2 students to revise this grammar point, which may be a bit difficult for those people who have just started learning English.
Carmen also provides this link to the web English Exercises for those students who wish to do more practice on this point.
Also remember that by clicking on the tag Subject questions on the right you will find more explanations and activities on the topic.