This post includes a Montessori Math Teen Board Lesson. The Teen Board is one of the first works introduced within the math sequence within linear counting.
Teen Board Lesson
Presentation I: Introduction to the Short Bead Stair
To being the Teen Board Lesson Invite the child, roll out a mat and bring the short bead stair to the mat: “This is the short bead stair.”
Get out the one and two bar. Give a three-period lesson. Place the two bars in an inverted triangle to the left of the work.
Bring out the 3 and 4 bars: “What do you think this is? What about this?”
Place them in an inverted triangle to the left of the work. Continue introducing each bar, practicing often with the 3-period lesson.
When all have been introduced, mix up the inverted triangle and ask the child to reassemble by looking for the one bar, then the two bar, then the three bar, etc.
Presentation II: Introduction to the Quantity for Teens
Place ten bars on upper left of the mat in a line and the short bead stair in an inverted triangle at the right. Invite the child to learn about teens.
Slide a ten bar down in front of you and the one bar beside it: “Ten and one more is eleven. Let us count to check.”
Take the counter and count the beads. Ask the child to count with you and to say: “eleven.”
Slide the first quantity to the left of the mat. Slide another ten and the two bar down side by side: “Ten and two more make twelve. Can you say twelve? Let’s count and see.” Ask the child with you. Emphasize eleven and twelve. Slide the quantities next to the eleven. Slide down another ten bar and the three bar and so on up to nineteen. At about fifteen stop and review what you have done before moving onto sixteen, etc.
If the child shows confusion over names, stop presenting new ones and practice the ones you’ve already introduced by playing games with the sequence, mixing up and hiding bars. Continue using the 3 period lesson.
Presentation III: Introduction to the Teen Symbols
“Today we’re not going to use the beads.”
Use a large mat. Arrange the teen boards one above the other in a vertical row.
Ask the child what the numerals on the board say: “Yes, they say ten, if we add one to ten, what do we get? Yes, we have eleven. This is how we write eleven.”
Slide the numeral one over the zero in the first ten. Trace it with your finger, say eleven and underline it with your finger. Invite the child to say eleven.
Continue adding numerals in this manner, a few at a time assessing the child’s interest and giving the three-period lesson often.
Presentation IV: Teen Boards with Beads
Place the ten bars in a line at the left with the colored bead stair in an inverted triangle below.
Point to the tens and ask the child what numeral that is.
Place a ten bar to the left of the first ten.
Place the unit bar to the right of it: “Ten and one more makes eleven.”
“Let’s count the beads. Eleven. This is how we write eleven.”
Slide the one tablet from the right side over the zero in the first ten.
Say “eleven” again and draw an imaginary line under it with your finger.
Repeat with the remaining numerals in a similar manner: form quantity, count it, form numeral, underline the numeral and say the numeral. Let the child take over as soon as possible. The child’s ability to take over the work is an assessment of his knowledge.
When the child reaches 19, have him read the numerals. Point to various ones, ask the child to tell you the name.
Wait to see if the child asks about the empty slot at the bottom. If he doesn’t, ask him what he thinks might belong there. Point out that twenty is two tens and it is not a teen.