## Teach your child how to count: numbers from 10 to 19

In my last article on numbers, I showed you how to teach your child how to count from 1 to 9, which helped him learn how to realize easy sums and subtractions.

I will now explain how to teach your child how to count until 19 with the Montessori approach.

A bar of 10 – a ten

Before you start the lesson, you must make sure that your child knows the numbers from 1 to 9 and their associated quantity.

To do so, you can use the pearl-bars used in previous lessons.

The Montessori pearl-scale

Show your child the “10 pearl-bar” that we call “a ten” (see photo) and have him count the pearls that compose it. Explain that “10” is the same as a “ten”.

Have him build the pyramid (or scale) of pearls from 1 to 9 and start the three-step lesson used in Montessori schools.

Eleven

First step:

Set the following things in front of your child on a small rug:

– A ten to which you add one pearl (a red one) and say: “this is 11” insisting on the fact that “one ten and one unit equals 11”,

Twelve

– Then take one ten and associate it to the 2 pearl-bar (it is green) and say: “this is 12” insisting on the fact that “one ten and two units equals 12”.

Thirteen

– Then take one ten and associate it to the 3 pearl-bar and say: “this is 13” insisting on the fact that “one ten and three units equals 13”.

Second step:

Leaving the three examples in front of your child, tell him:

– Show me “twelve”, show me “eleven”, then show me “thirteen”.

If he answers correctly, mix the examples and ask the same three questions once again.

Continue this exercise a number of times.

Concrete presentation of 11 – 12 – 13

You can ask him to give you thirteen, give you twelve… or tell him to use the bars and show you number 11, number 12… or take away 13, take away 11 and so on…

Continue until you are sure that he has associated the number to its quantity.

Continue until you are sure that he has associated the number to its quantity.

A confident child

If he has difficulty handling three new notions at a time, teach him only two notions; if it is still too difficult, teach him only one notion. The most important thing is that the child progresses at his own rhythm. By putting him in difficulty or by showing him his error, you risk stopping that progression.

Never show concern or irritation if your child does not understand the first time round. This would only stress your child, would only lead to more errors, or have him lose his self-confidence.

Concrete presentation of 11 – 12 – 13

Third step:

Isolate the group of numbers to show your child only one group at a time and ask the question “what is this?”. If he answers correctly, take that group away and show him another one. Ask the question “what is this?”. Do the same with the third quantity.

Conclude the lesson by putting the three quantities in front of the child. Tell him “today, we have learned 11 (show him 11), 12 (show him 12), 13 (show him 13).

The tens in abstract – The Seguin tables

You can also propose to play games: “clap your hands eleven times”, “clap your hands thirteen times”…

On another day, associate these quantities to their symbols.

First, verify that your child remembers what are “11”, “12” and “13”.

In a Montessori school, we use “the Seguin tables”. We use two boards that we set one on top of the other on a small rug on which appears number “10” nine times (see photo). With these two boards, we use numbered bars from 1 to 9. We can slide a numbered bar on the 10 and form 11, 12 and so on… until 19.

11, 12, 13 in abstract

Show your child number “10” and start a three-step lesson.
As a first step, tell your child “this is 10”. Take the “1 pearl bar”, set it on the space dedicated to “10” and say: “10 and 1, equals to 11”, “10 and 2, equals to 12”, “10 and 3, equals to 13”.

As a second step, ask him: “show me 11”, “show me 13”, then “show me 12”. Shuffle the numbers and start again. You can also tell him to “make 12”, “make 13”, “make 11”. Repeat a number of times until you are sure that the child recognizes the right symbol.

Go on to the third step of your lesson:

11 – 12 – 13 association of concrete and abstract

Show your child a symbol and ask “what is this?”. Repeat the questions showing him other symbols.

At the end of the lesson, conclude by telling him and showing him the corresponding symbol: “today, we have learned the symbols of 11, 12 and 13”.

On another day, ask your child to associate the quantity to the corresponding symbol. Remember that you must always teach the concrete version before the abstract one. You do not need to do things for your child. He can do it on his own. He does not have to do everything with the symbols in the right order.

16 – 17 – 18 – 19 association of concrete and abstract

If you do not have access to Montessori material that is extremely expensive, you can build it at home. Build nine bars with number 10 (use cardboard or use paper and cover with plastic) and build bars with numbers from 1 to 9. Set “1” over the zero of number “10” and say “11”. Set “2” over the zero of number “10” and say “12”. Set “3” over the zero of number “10” and say “13”.

This way, you can teach your child the numbers from 11 to 19. Repeat that numbers from 11 to 19 are made of a ten and units from 1 to 9.

To help your child master the numbers in a more sensorial way, you can write the number of the tens in blue, and that of the units in green. This way, you will teach him the place of the digits in a number (unit, ten, hundred, thousand…)

Exercises with numbers

You can then propose different exercises. For example, on the left hand side of a piece of paper, draw the tens and the units placed aside and on the right side of the paper, write the symbols and ask your child to draw a line between the symbol and its quantity (see photo).

He can also draw the tens, cut out the units and stick them under the symbol.

Do not worry if your child takes time to remember eleven, twelve, thirteen, fourteen and fifteen. It is quite normal for young children.

Once your child knows how to handle numbers from 11 to 19, you can go on to numbers 20 to 29. I will show you how in my next article.

Sylvie Rousseau-d’Esclaibes