Final answer:
John's problem was not knowing what to take for show and tell, and the solution was his mother's suggestion to take the ribbon won by his dog.
Step-by-step explanation:
The problem in this scenario is that John did not know what to take to school for show and tell. The solution is that his mother suggested he take the ribbon his dog won at the pet parade. This provides John an item with personal significance and a story to share, making it an ideal choice for show and tell. Furthermore, this situation highlights the effectiveness of practical suggestions from parents, and the importance of show and tell as a storytelling exercise in school.