Most children know exactly what to do when let loose in a wood or on the beach, but a few tools always help when it comes to exploring.
Nick Baker's Habitat Explorer series of books ( Seashore; Rivers, Ponds and Lakes; Gardens and Parks and Forests and Woodlands) has lots of tips on making nets and traps for sea creatures, collecting seeds in woods and rearing pond snails. Easy to read with plenty of photographs, they are a great addition to any nature walk.