To find the GCF of 24 and 36, we need to list all the factors of each number. For 24, the factors are 1, 2, 3, 4, 6, 8, 12, and 24. And for 36, the factors are 1, 2, 3, 4, 6, 9, 12, 18, and 36. Now, let's see which factors they have in common.
As we can see, the common factors of 24 and 36 are 1, 2, 3, 4, 6, and 12. But, we're looking for the greatest common factor, so we need to find the largest number in this list. And, the winner is... 12! So, the GCF of 24 and 36 is 12.