We're learning our numbers up to 30 in French class and today I had the students interview each other to make a phone book of the class.
I gave each student a small card with a French first name and a French phone number. I gave them different names than the French names they use in class so that they might have to practice saying, spelling, and writing unfamiliar names. Students had to ask each other for their name, how to spell the name, and what their phone number was. Then they met a new partner and recorded more in their "phone book." We spent about 15 minutes on this and it was our first extended period of time in class that I expected students to speak entirely in French. They did pretty well; I heard bits of English, but overall they tried hard not to!
Here's an example of the cards the students used: