Through reading a novel in Spanish class, my students have seen the imperfect subjunctive many times. To give them more exposure with the imperfect subjunctive, we did a quick activity with IF CLAUSES.
1. I wrote the typical sentence on the board...Si tuviera 5 millones de dólares, yo... and wrote possible answers. I continued by writing the verbs only of other examples as I said the sentences, ...si hablara cinco idiomas, yo trabajaría...
- we discussed the second part of the sentence (the conditional) because they already had learned this the previous year of Spanish. Then I showed them how fuera, tuviera, hablara, durmiera, was formed, which took only a minute or two. Resist the temptation to show umpteen examples of irregular verbs - they don't need it know, nor do they want to hear it at this point. Keep the emphasis on communicating meaning.
2. Then I gave each student two pieces of paper. On one paper they wrote the first part of the phrase using IF + imperfect subjunctive (but I didn't call if by that name); on the second paper that said what they WOULD do if the first part of the sentence were true or were to happen. I reminded them that I wanted interesting and creative sentences; boring sentences were not an option.
3. I collected the papers as two separate piles and redistributed them, making sure the original match was not together.
4. Students read their new sentences and we discussed or commented on each. It wasn't necessary for me to call on students to read their sentences - they wanted to read them to their classmates.
I'll let that activity digest a little and then approach the imperfect subjunctive from a different angle.