This is one of these “easy pieces” that is not easy at all. In fact, there are many things that are quite advanced. Kabalevksy was a genuis Russian teacher who was also a famous composer, so even his “simple” music is complex and sophisticated. When we see “pieces of children”, the children he was writing for were incredibly talented young children who were in no way average children. When you can play anything by Kabalevsky, even the simplest things he wrote, you are on your way to being an advanced player.