This interviewing activity is perfect for supporting generalization for students who have mastered "ch" or "j" during structured activities in the speech room.
Just print the first 2 pages of this document double-sided and cut in half along the dotted line. Have your students survey staff members in the front office, peers in their classroom... whoever is available during your session. Your students can tally their interviewees' answers in the columns on the right, so you can discuss their results afterwards (creating another opportunity for using their speech sounds in conversation). They can also turn their paper over and rate their own productions.