CH-ease (sh/ch discrim.) Match

The "ch" and "sh" sounds in English are both made with lips puckered and the front teeth narrowly apart. But the "ch" is made with the tongue widening and stopping the intraoral airflow momentarily and releasing it suddenly (as in a sneeze). The "sh" is made with a widened, raised tongue, but with no stoppage of airflow. (Librarians take note!) Can you or your students say and match the words that sound the same except for these sounds??