Simply fill in the blanks of this diminutive volume and voilà: it becomes a personalized gift your #1 teach will read again and again. Make it as educated, eloquent, or elementary as you please! Gifts for teachers that totally make the grade. Fill in the blank gift books: more beloved than book reports! Hardcover with removable clear plastic jacket; 4.5 × 3.25 inches; 112 pages. Knock Knock is an independent maker of clever gifts, books, and whatever else we can think up. Our mission is to bring humor, creativity, and smarts to everyday life. Put the fun in functional with Knock Knock stuff.