American football is fun. Crossword puzzles are fun. Math and science-fun? These crossword puzzles mix clues about football with math and science facts appropriate for students in grades 5 - 12. Who knew that the answer to the clue "A single-celled organism that lacks a nucleus" would rely on the answer to "Football position Pete Gogolak played in 1964"? Where else can the correct answer to the clue "Which is bigger: one liter or one quart?" be dependent on the answer to "How many downs are there in Canadian football?" Crossword puzzles--a good habit at any age (Developed by a certified teacher)