What is Thomas Jefferson signing? Focus on American history with this cross-curricular math puzzle. Learners utilize addition and subtraction skills to solve the mystery of the Fourth of July. All numbers are 3-digit, and there are no negative numbers. For each of the twenty-seven problems they solve, they get one more letter toward the final answer. Consider playing this as a "Wheel of Fortune" type game with the whole class! There are two pages with the same level math but differing order.