In the Harry Potter universe, there's not really any need to text. People can use floo powder to talk to other wizards and witches through their fireplace and they can apparate at will. But what might happen if the characters from the Harry Potter books started texting one another?
Students received notice that they have gained entrance at Uagadou from Dream Messengers, sent by the headmaster or headmistress of the day. The Dream Messenger would appear to the children as they slept and leave a token, usually an inscribed stone, which would be found in the child's hand on waking. This was the only such school that employed this method of student selection.