A modular area wall system for constructing area wall assemblies at a jobsite. The area wall system provides modular sections of varying heights, each provided with a connection plate and a strengthening rib to allow them to be connected to one another in a simple and secure manner. By providing the strengthening rib in overlapping engagement with another area wall section, lighter material of more inexpensive construction may be utilized to reduce the overall cost and weight of the resulting assembly. The system may also be used with sections of varying depth to create a tiered area wall, using teachings of the present invention.