Six Seven 67 Math Challenge: Order of Operations. Bring the viral fun of 6-7 Math into your classroom. Add arithmetical symbols between the sixes and sevens to make each of the target numbers. You may use plus, minus, times, and divide symbols, as well as parentheses and brackets for grouping. Inspired by Math = Love. This resource includes:- The printable version in PDF + the answer key. Click the GREEN STAR at the top of my store to follow me and be informed about my new products and sales.