When Nellie shows Laura the large silver cup that would be given as a trophy for the race, crew members can be seen standing behind Laura in the cup's reflection.
When Mrs. Oleson is telling the family that Willie will ride Nellie's horse in the race, she places a piece of pie in front of him. After he takes a bite, she is shocked he is eating it and tells him no sweets. There was no need for her to give him the pie just to take it away again.