In Ireland, grinds are private tuition; a major industry in Ireland, particularly at secondary school level. "Grinds" is a Hiberno-English term which is used variously to refer to both the lesson and the teacher, although the latter usage is less common. It is generally used in the plural.
Origins
Ireland was traditionally an agricultural and farming community so perhaps this is where the word ‘grind’ started. Grinding stones were used to produce flour by hand in ancient agriculture and evolved along with the development of different kinds of mills. From hand quern mills to grist mills powered by water, wind or steam, grinding stones remained an essential tool until the end of the 19th century, when roller mills using metal rolls to grind grain were developed. The term ‘keep your nose to the grindstone’ was commonly used to mean ‘apply yourself conscientiously to your work’.‘To grind’ in education generally means to ‘instil or teach by persistent repetition’. Charles Dickens referred to Mr Gradgrind in his novel Hard Times.
Prevalence
Grinds in Ireland are a major component of educational life. Many Irish students will have "grinds" before sitting either one or both of the two major state exams, the Junior Certificate and the Leaving Certificate. Grinds are a multimillion-euro industry in Ireland. Availability of online resources, such as 625points.com and studynotes.ie, has led to a decrease in demand for grinds in recent years. In 2012, the Office of the Revenue Commissioners launched an investigation into a perceived failure of some teachers to declare extra income from giving grinds for tax purposes. The teachers' union ASTI denied that this is a widespread problem. The terms grinds had also become popular at the college/university level. The cost of grinds varies per subject area. Some schools such as Ashfield College, Bruce College, Institute of Education, Leinster Senior College, and Yeats College which offer the Leaving Certificate as a single year course are called grind schools.