One of my first illustration assignments was for a book about gardening activities with children. At that time, most books for children were illustrated with black and white art so I made pencil drawings. Here is one of the activities meant for younger children. It would work well with pre-school or kindergarten children.
Materials needed: Carrot, string, soil, alfalfa or cress seeds.
From Children’s Gardens: A Field Guide for Teachers, Parents and Volunteers by Elizabeth Bremner and John Pusey, Illustrations by Caroline Arnold