The teen board is a math material that helps students connect an amount with it’s symbol.  Students use the bead bars and the teen board to count out and form the symbols for the teen numbers.  For each ten, they place a ten bar.  For each number of units 1-9, they place the corresponding bar, slide in the digit, and count the total beads.  In this manner, they recognize that one ten and one unit makes the number eleven, represented as 11, etc..  For information on the introduction of the teen board, click this link to infomontessori.com.