"El niño quiere dibujar en la pizarra."
Translation:The boy wants to draw on the chalkboard.
A pretty common way to say this (in Australia at least) is to just say 'board'. "I'm going to write it on the board". You would only specify if there was a choice of boards (blackboard/whiteboard). I don't think it's ever called a chalkboard in Australia.
And most of our blackboards at school were actually green. We never use 'chalkboard' in the UK. Doubt there are any blackboards left in schools nowadays.
I and do not see why "chalkboard" is accepted while "blackboard" is not. Cambrige dictionary gives them as synonims.
I wrote -blackboard- which is given on the hover hints yet my answer was marked wrong.