Add spaces: Iftheaveragestudentcouldn'tcopewiththemathematicsthatPeircewaspresentingthemwith,thenhedecideditwasbetterhesawonlythemoretalentedanddedicatedstudentscontinuewithmathematicsbeyondtheirfirstyear.
If the average student couldn't cope with the mathematics that Peirce was presenting them with, then he decided it was better he saw only the more talented and dedicated students continue with mathematics beyond their first year.