Abstract: Systems and methods for preparing construction material mixtures. A container can include a flexible body having an interior for receiving and holding construction material mixture components to be mixed. The construction material mixture components can be mixed in the interior by rotating a mixing tool. The flexible body is collapsible for forcing the construction material mixture out of a mouth of the container. The flexible body can be everted to facilitate cleaning the interior of the flexible body. The system can also include a stand, a mixing tool, a funnel, and/or a measuring cup.