GCF and LCM: Crack the Code

Give your learners practice finding the greatest common factor (GCF) and the least common multiple (LCM) with this fun code-breaking worksheet! Designed for sixth-grade learners, this worksheet builds number sense as it challenges students to use their knowledge of factors and multiples to solve a fun riddle. Students are first tasked with finding the GCF of six sets of numbers and the LCM of eight sets of numbers, each set progressing in difficulty from two to three whole numbers. Then they will use the solutions to crack the code at the bottom of the page. For more targeted GCF or LCM practice, check out the GCF: Crack the Code and LCM: Crack the Code worksheets.