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From dr trapp:
Practice all four basic arithmetical operations in 10 appealing gamesPractice additions, subtractions, multiplications and divisions separately or in random mode depending on personal selection and game typeLevels correspond to elementary school levels 1-4 covering numbers up to 20, 100, 1000 and 100000Levels can be selected based on personal skillInfinite number of different exercisesSelect a time limit for the problem sets to simulate test situationsMultiple users can be addedGraphical evaluation of scores and times of the last 10 exercises to monitor progressEnglish/ German/ French/ Spanish/ Italian