Counting by twos is sometimes called "skip counting" because every other number or count is skipped. Each count is two more than the previous count.

If you counted by twos and started with 1 then the blue boxes would have the counts (1, 3, 5, 7, 9, 11) If you counted by two's and started with two then the white boxes would have the counts (2, 4, 6, 8, 10, 12).

If you counted by twos and started with 1 then the blue boxes would have the counts (1, 3, 5, 7, 9, 11)

If you counted by two's and started with two then the white boxes would have the counts (2, 4, 6, 8, 10, 12).