Kendra's kinetic energy is highest at the lowest point of the hill, just before she comes to a stop. As she rolls down, her potential energy (due to her height) is converted into kinetic energy (the energy of motion).
At the top of the hill, her potential energy is at its maximum and her kinetic energy is zero. As she descends, her potential energy decreases while her kinetic energy increases, reaching its maximum just before she reaches the bottom of the hill. As she rolls up again or comes to a stop, her kinetic energy decreases again.
So, to summarize: Kendra's kinetic energy is highest at the lowest point of the hill.