Last spring, bees came to our balcony. There were only a few at first, but after a week there were hundreds. My mother wanted to call someone to remove them, but my father said we should wait. The bees built something under the roof of the balcony. It was grey and round, like paper. We could not use the balcony for two months, so we watched them from the window. Our neighbour told us they were not honey bees. They were wild bees, and they were disappearing everywhere. She worked at a school and knew about these things. In August, they left. All of them, in one afternoon. My father climbed up and took the nest down carefully. It was empty and very light. It weighed almost nothing. He gave it to the neighbour, and she took it to her school. Now it sits in a glass box in a classroom, and about two hundred children a year look at it.