An experimental group is the group in an experiment that receives the variable being tested. One variable is tested at a time. The experimental group is compared to a control group, which does not receive the test variable. In this way, experimental groups are used to find answers in an experiment.
1 At around 9 months of age, babies begin to pull themselves up to a standing position. 2  By 10 months of age, a baby should be able to grasp objects with thumb and forefinger.
By 12 months, most babies will have their permanent eye color, although Dr. Fredrick says that some children's eye color may still change up until age 6, though this occurrence is rare and the change won't happen overnight. 1  Super Fun Baby Toys to Keep Baby Stimulated.