In the Student/Teacher Achievement Ratio (STAR)study,why Did the Researchers Create

Multiple Choice

In the Student/Teacher Achievement Ratio (STAR) study,why did the researchers create two separate intervention groups?

A) The sample size was too large to only accommodate one intervention group.
B) The study could also evaluate the effectiveness of a cheaper intervention-teacher's aides.
C) The central evaluation question was whether larger class sizes improved student learning.
D) Since the cost of the project was so low,researchers evaluated multiple interventions.