Based on the scenario, determine if this investigation was an experiment.
Yes, this investigation is an experiment. The teachers observed and compared the two groups. There were test and outcome variables but no controlled variables.
Yes, this investigation is an experiment. The teachers observed two groups and recorded data. They did not manipulate variables.
No, this investigation is not an experiment. There are no variables. There must be a test variable and an outcome variable.
No, this investigation is not an experiment. There are no controlled variables. In experiments, only one thing may be changed. All other parts must stay the same for all groups.
No, this investigation is not an experiment. There are no controlled variables. In experiments, only one variable is manipulated while all others remain constant to establish a cause-and-effect relationship. Since the scenario indicates a lack of controlled variables, it fails to meet the criteria for an experiment.