Try to limit your verbal language around kids with echolalia. Alot of times they're repeating, because they know they are suppose to say something, just not quite sure what to say. You can "shape" echolalia by saying an appropriate phrase during the activity knowing they are going to repeat it. For example, when blowing bubbles, you can say "blow a big bubble", child repeats, and you say "Okay!" and blow a big bubble. Start in structured settings and move to other environments to promote generalization. Good luck.