Create a pencil illustration of a cheerful farm scene featuring friendly animals. The artistic style should be simple and easy to follow, with clear outlines and minimal shading to allow children to easily paint within the lines. The background features a classic red barn, a wooden fence, and a field of green grass. The foreground includes a variety of farm animals such as a cow, a pig, a sheep, and a chicken, all drawn with smiling faces and approachable expressions. Each animal should be large enough to provide ample space for coloring. Use a soft pencil to create smooth lines and ensure the composition is balanced and inviting. The focus points are the animals, and the background elements should be less detailed to avoid overwhelming young artists.