This study examined the effect of language on children's cognitive representation of number. The sample for the study consisted of 90 Arabic speaking children with a mean age of 80 months. Children were interviewed individually and asked to represent written two-digit numbers using base-10 blocks. A new approach for testing the linguistic relativity hypothesis was used. The results of the study revealed that language played an important role in children's cognitive number representation. On the other hand, the results support the argument that the instructions given with the task alter children's performance on it. This study suggests that language may explain the cross-cultural differences in mathematics achievement. However, the disadvantage that the language might place on children can be overcome with well-planned instruction.