They will astound you everytime how hard they will work on something that they are truely interested in. It is alright to be at a challenging level if they initiated the interest. Affirm their accomplishment step by step over and over again. Recitals are an opportunity for the other students to hear something that they would like to work on and accomplish. We were not born with a library of musical exposure.
Variety is the spice to learning and growing in music education.
Put yourself in their shoes. If not, approach it from a different angle. Be creative and have fun teaching. Your students will, too. As a private teacher, you have a huge impact on a child's life.