Going fishing with bears, swimming races with octopuses in the sea - this is how practicing becomes a pleasure! Regular practice is essential to gain proficiency in basic mathematical operations. The enchanting calculation animals motivate children to engage with the exercises. To ensure that each child can be supported according to their abilities, all worksheets are available for both the number range up to 20 and the number range up to 100. This way, children can work on the same theme in different number ranges. Topics: Addition, subtraction, complementing, reducing, doubling, halving. Content: 42 worksheets in the number range up to 20 and 42 worksheets in the number range up to 100, along with solutions. Suitable for: Basic level, 1st/2nd grade.