In examining the effects of altering the length of the school year, researchers did not specify particular factors for these alterations in specific schools or districts.
Wrth ystyried effeithiau newid hyd y flwyddyn ysgol, ni wnaeth yr ymchwilwyr nodi ffactorau penodol a oedd y tu ôl i’r newidiadau mewn ysgolion neu ardaloedd penodol.