Number sense is one of the areas within mathematics, and learning number sense through problem solving leads to an understanding of numbers for the students. Which tasks teachers use is important and today teachers can get many exercises via forums online. The purpose of this study has been to study what character the assignments have within the number sense area on the website lektion.se, how they are designed and what they is being treated. In order to respond to the purpose, quantitative content analysis has been carried out using the Taflins (2007) framework diagram to categorize the data according to character. A qualitative content analysis has then been used to respond to the final parts of the purpose, to find patterns within and between the categories. The result show that only a small part of the exercises in the sample had the character of being a problem task. Most of the tasks trained different skills through the four counting methods addition, subtraction, multiplication and division