I have used this for a few years now and have found it to be very useful. There is a small section of a train timetable on the first page with some examples of "How many times a day ...?" questions as well as "How often does ...?" and "How long does it take ...?" along with some small explanations of the grammar. Once all the grammar has been done, the students can practice asking questions in pairs about the train timetable on the next page. There is also a dice game for the slower students and a tiny lesson plan just in case it isn´t very clear.