<p>Using the Addition Strip Board, the child practices using the sequence of addition combinations 1-9, and begins the process of memorization of the addition tables. The material is composed of hardboard chart 12 squares with the numbers 1-18 printed across the top. Stored in a wood box are the strips used for the exercise, nine red strips divided into squares and nine solid blue strips, both printed with the numerals 1-9. (For age 3-12)</p>