More and less is an important concept for children to understand. Children are usually able to become acquainted with the concept of more as toddlers. In preschool and kindergarten, they will continue to show their understanding through comparing groups as more or less, sometimes called more or fewer. Before you begin teaching more and less, you may want to begin by reviewing one to one correspondence. This is just 1 of 4 worksheets available on my site. Enjoy!