The biggest part of the brain is the cerebrum. The cerebrum is the thinking part of the brain and it controls your voluntary muscles. It also helps you reason, like when you figure out that you’d better do your homework now because your mom is taking you to a movie later. The cerebrum has two halves, with one on either side of the head. Scientists think that the right half helps you think about abstract things like music, colors, and shapes. The left half is said to be more analytical, helping you with math, logic, and speech. Scientists do know for sure that the right half of the cerebrum controls the left side of your body, and the left half controls the right side. Source: https://kidshealth.org/en/kids/brain.html