While numerical skills are fundamental in modern societies, some estimated 5-7% of children suffer from a mathematical learning disorder, called developmental dyscalculia (DD). Nevertheless, universally valid diagnostic instruments are still lacking, as all current DD test batteries are based on language instructions. Consequently their measurements are tightly linked to the specific language context of test administration and thus their results cannot easily be compared across countries. The present study is the first pilot study of a research project that aims to develop a test for basic math abilities that does not rely on language instruction and minimizes language use. To this aim, video and animation based instructions were implemented on touchscreen devices. A first version of the application has been tested with a sample of first grade children in Luxembourg’s fundamental schools, of which half used the same application but with traditional German instructions. First results indicate that performance in the experimental group was similar to the control group using verbal instructions. Relationships between linguistic background and the sample’s performance on one hand and qualitative usability aspects of nonverbal task instruction and tablet use with young children will be discussed
