Description :Using the number line, adding and subtracting up to 20 becomes a game!How is the number line used?The children locate the number on the number plate in the first tile and depending on the operation (addition or subtraction) they \�€go up\�€ or \�€go down\�€ as many numbers as the second tile writes. In this way they slowly move from counting with their fingers to mental acts.Contains:36 Tiles comes in a Potli Pouch(0 to 10) 2 sets(11 to 20) 1 set2 addition tiles2 subtraction tilesBe sure that there are many ways to use it! An amazing tool in the hands of the teacher and the parent.