Gosh...this is first grade. I realize my first grader's experience at Title 1 school is not really the norm, but there, a presentation by the kids would last maybe 1 min and consist of a lot of nothing. I think it's time to rein this in, with the knowledge that she learned and experienced. I would insist on finishing it up and give her a little time to learn and practice her speech and say--hey, great. Unless she is at a private gifted school or something, she is bound to have overproduced. In the future, I would work on planning a reasonable plan of work and then she can extend on her own time if there's desire. It will be important later.