Shanthi mantra [prayer] from kathopanishad.

Om! Sahana vavatu!Sahanau bhunakthu!
Sahaveeryam karavaavahai!
Tejas vinaavadhitamastu ma vidvishaavahai!

Om! Shanthi, shanthi, shanthihi!

Om! May he protect us!
May he nourish us!
May we work together with all our strength and energy!
May our study be vigorous and effective!
May we not argue or quarrel with each other!

Om ! Let there be peace in me !
Let there be peace in my environment!
Let there be peace in the forces that act upon me!