The invention relates to methods, compositions, kits and systems for determining one or more cement material properties. In one variation, a color change agent is introduced into bone cement to allow a physician to determine when a cement has the desired viscosity for insertion into a patient. In another variation, the composition comprises one or more curable bioactive agents and one or more color change agents. The curable bioactive agent(s) may be one or more bone cement(s). These Bone cements contain a color change agent that allows a physician to tell when the cement has reached the property viscosity for insertion of the bone cement into a patient at the bone site.