Mae llyfrgelloedd ledled Cymru wedi ymuno â rhaglen Hwyl o Haf Llywodraeth Cymru i ddarparu mwy o gyfleoedd a gweithgareddau byth ar gyfer plant dros gwyliau'r haf.  Yn rhedeg bob dydd o'r gwyliau hyd at fis Medi, maent i gyd wedi'u cynllunio i agor llygaid a dychymyg plant i'r wyddoniaeth o'u cwmpas drwy ddewis eang o weithgareddau wedi'u hysbrydoli gan STEM, hwyl a gemau am ddim a rhaglen o dros 50 o ddigwyddiadau am ddim dan arweiniad hoff awduron plant.
Libraries across Wales have also joined forces with the Welsh Government’s Summer of Fun programme and, inspired by the SRC Gadgeteers, are providing children with even more STEM related events and activities over the summer holidays. Running each day of the holidays right through to September, they’re all designed to open children’s eyes and imaginations to the science all around them via a menu of hands-on STEM inspired activities, free fun and games and a programme of over 50 free events led by favourite children’s authors.