Embodiments of the present invention relate generally to fiberizable glass compositions comprising boron oxide at least one rare earth oxide in a molar ratio of rare earth oxide to boron oxide ranging from 0.01 to 0.33. Other embodiments of the present invention relate to methods of inhibiting boron volatization from glass compositions comprising boron oxide by adding a rare earth oxide to the glass composition before melting the glass compositions. Still other embodiments of the present invention relate to glass fibers formed from the fiberizable glass compositions of the present invention, and polymeric composites and printed circuit boards made therefrom.