I am guessing this is preschool?
No she has finished pre-school. She went to pre-school for two years and is now moving onto 'big school'. She will be at St Thomas' probably for the next 8 years and then they will move her to a high school. That may or may not be a boarding school. I have read that Catherine doesn't want the children to go to boarding school at all and there are excellent private day schools very close to where they live at KP anyway.
George has been at St Thomas' for two years now and so has another six years there and no doubt Louis will join them in about three or four years time.
As for photos - I have heard that first day photos will be released, probably taken by Kate, but that there may not be any actual footage of her arrival as there was with George when William took him to school (and Frederick Windsor took Maud on the same day).