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.
Over the next ten to 12 weeks, you will notice your baby following moving objects and recognizing things, especially toys and mobiles with bold, geometric patterns. As their color vision begins to develop, babies will see red first â they will see the full spectrum of colors by the time they reach three months of age.