The Micro System
The micro system's setting is the direct environment we have in our lives. Your family, friends, classmates, teachers, neighbors and other people who have a direct contact with you are included in your micro system. The micro system is the setting in which we have direct social interactions with these social agents. The theory states that we are not mere recipients of the experiences we have when socializing with these people in the micro system environment, but we are contributing to the construction of such environment.
The Mesosystem
The mesosytem involves the relationships between the microsystems in one's life. This means that your family experience may be related to your school experience. For example, if a child is neglected by his parents, he may have a low chance of developing positive attitude towards his teachers. Also, this child may feel awkward in the presence of peers and may resort to withdrawal from a group of classmates.
There ya go