Bring your little ghouls and goblins in their favorite costumes to the Main Street historic district in St. Charles for trick or treating from Main Street merchants.
3 to 5 p.m. along Main Street in St. Charles. Free.
More information: discoverstcharles.com
Engage your young scientist in science-related learning at the Saint Louis Science Center's Preschool Science Series. Through interactive stories and hands-on exploration, children learn about science, as well as language, problem-solving and social skills.
Kids can use their observation skills to discover the wonderful biodiversity in their own communities while meeting animals that make their home in Missouri and Illinois.