The present disclosure describes a resin cassette for an additive manufacturing apparatus. The resin cassette includes a light-transmissive window, a frame connected to and surrounding the window, and at least one dame connected to the frame. The frame and window form a well for receiving a light polymerizable resin. The dam extends over and continuously contacts the window and partitions the well into a plurality of independent build regions, each independent build region configured for receiving different light polymerizable resins. Additive manufacturing apparatuses and methods of concurrently making three-dimensional objects are also described.