Methods of making unsaturated polyester compositions are provided and include reacting: (i) plant and animal oil triglycerides, an alkyl ester of a saturated or unsaturated fatty acid or mixtures thereof; (ii) a difunctional, or polyfunctional glycol or mixtures thereof; (iii) a difunctional or polyfunctional acid, their anhydrides or alkyl esters and mixtures thereof; (iv) a strained cycloolefin; (v) a component(s) that function as a compound capable of initiating polymerization at high temperature and which is stable at room temperature; and (vi) low profile additives, fillers and reinforcements.