“…An intriguing hint, possibly providing a lead toward an explanation for the high number of "no significant differences" findings, is contained in Lambert, Goodwin, and Wiersma's (1965) discovery that in the second year of their study some team-taught pupils scored significantly higher than solitary-teachertaught pupils. While admittedly very fragmentary evidence, this finding may indicate that a teaching team requires a necessary "percolation time" before it becomes an efficient instructional unit.…”