Systems and methods in accordance with embodiments of the invention determine the effective toughness of a given material, and also implement materials possessing improved effective toughness values. In one embodiment, a method of determining the effective toughness of a material includes: causing a crack to propagate through the material; where the relative constant velocity and the relative overall direction are prescribed and maintained for the duration of the propagation of the crack through the material; measuring the energy release rate of the crack as it propagates through the material; and defining the effective toughness of the material as the maximum value of the measured energy release rate.