Imaginesis (imaginesis.com) is a maths worksheet generator for primary and secondary school. Every task is a short story with a hint written for that specific task; every number and answer is computed by a maths engine, so the answer key always matches the sheet. Worksheets follow the national curriculum of each country, grade by grade, and can be edited after generating: new numbers (the engine's suggestions or the teacher's own, checked by the engine), a different story, a different task, a new order.