The experiment would be established to determine the influence of the drug in reducing children's hyperactivity. With that, we can say that the independent variable would be the drug, and the dependent variable would be the reduction of hyperactivity.
To perform this experiment, a sample of 30 children diagnosed with hyperactivity would be established. These children would be divided into groups containing 3 children. Each group would be composed of children of the same age, but children in one group would be different in age from children in another group.
In each group, two children would receive a recommended dose of medication, while the other child would receive a dose of placebo (they would receive a dose of other material, which is not the medication and has no effect on the body). The child who received the placebo would be the control. Neither children nor parents would know who is receiving the placebo and who is receiving the medication.
The experiment would last for 3 months and it would be necessary for parents to note the changes in their children's hyperactive behaviors, if any.
The evaluation of the result would be done by comparing the notes of the parents in each group of children. It would be noted if there were significant differences between the behavior of the children who received the medication and those who did not, in each group. Then an assessment would be made, which group had the most significant behavioral differences, to assess whether the drug is more efficient at a given age.