I'm a student from Manchester which studies in Leeds. The cheapest possible way of traveling to and from said destinations is possibly this deal I found. You must enter 'Manchester Victoria' as either your departing station or arriving station and 'Leeds' vice versa. You will be given train times in which you must scroll through and find the £3 trains. Northern advance tickets are usually available the night before at the same price so no need to book till the day before travel. The trains take around 30-40 mins longer than a usual transpenine train but considering the money you're saving if you was to take the journey often its well worth it in my opinion. Note that you must get the train you select and these are not anytime tickets. If you miss your train you will not be eligible for a refund. Overall this has saved me quite a bit of money as a the journey would usually cost around £20.