Campers and bird-lovers will share the rich pleasure that Brian Vogel and his younger sister Jenny derived from the unusual gift Aunt Laura sent -- a bird-feeding station. Throughout the year Brian and Jenny recorded the visits of feathered friends, to learn of the winged world. Each season brought surprises. Bits of yarn they left to help with nest-building turned up in winter in an oriole's nest. When Christmas came round again, the children decorated an evergreen for the birds, with pine cones filled with peanut butter and chickadee pudding poured into grapefruit and orange shells. Marjory Bartlett Sanger is an editor for the Massachusetts Audubon Society. Christine Price imparts seasonal charm with black and white sketches to spark or nurture love for birds and wild life. (A useful appendix rounds out tips on feed and feeders, birdhouses and their dimensions, keeping a notebook, birds' nests, planting for birds, state birds and flowers, and recommends additional reading for fledgling ornithologists.