When teaching the value of double-digit numbers in my classroom, I noticed that my students often became confused with 11, 12, and the rest of the -teen numbers. This was a puzzle to me, and I was determined to solve it. After research and applying what I know about how young students learn, I realized this was not a numbers problem—it was a language problem!
In various languages around the world, there are simple words for -teen numbers. Eleven translated is 10/1, twelve is 10/2, thirteen is 10/3, etc. The numbers continue, 21, 22, 23—all the way to 99— just as in English. This was an “aha” moment for me! Counting easily from one to 10, then having to switch to “-teen” counting, was confusing my young students.
Young learners are very literal. They didn’t understand the concept of 13, but could easily understand that 10/3 meant one set of 10 and 3 more. It was a simple change that made a big difference in their understanding of the “-teen” numbers!
So I started teaching the numbers between 10 and 20 in tandem. Students practiced, understanding that another way to say 11 was 10/1, twelve 10/2, thirteen 10/3, and so on.
Now, when teaching the numbers 11-19, I always teach them in tandem. Young children love to be able to say “another way to say 15 is 10/5!”
This is something that parents can easily do at home, to help young students overcome this mathematical English language issue.