What's going on here? There's a scrawny cow (sans udder and horns, we would have said a horse) with a mind to build a house; and a frog who keeps helping/interfering; and some letters (PUSH, DIG, etc.) out of ""Sesame Street"" which suddenly appear and metamorphose, film-cartoon-like, into props. And through page after page of otherwise wordless cartoons, the dopey, determined cow is undone by the fiendish frog. Saturday-morning slapstick (in black-and-white and green) with an educational gloss.