The Learning in Science Project (Primary)--LISP(P)--investigated the questions and explanations primary children have about spiders. The data comprise 112 questions and 104 explanations (included in appendices) offered by children after being shown a picture of a spider. Additional data were collected during individual interviews with 18 students. The majority of questions raised by students were grouped into these categories: spider features; silk or web; food or prey; young or reproduction; species; poison; habitat; and origin, life, and death. Selected questions asked and some of the explanations offered in each of these categories are analyzed. They include an analysis of answers to the questions "Why do spiders have so many eyes?" and "Why does a spider's web look invisible to a fly?" Strategies used by children to gain insight to help with their ideas about spiders are also discussed. They include guessing, generalizing from a limited experience, recognizing when they have insufficient knowledge to form or offer an idea, recalling relevant past experiences, reasoning by analogy, and gaining ideas from such sources as books or television. Although these strategies must be regarded as tentative (being drawn entirely from comments children provided during interviews), they offer leads to future research into this aspect of children's thinking. (JN)