Still a deal but be warned, I'm guessing the amount of disuption/'improvements'? over the summer to keep the lovely economy afloat during the mon-friday days might have you pulling your hair out £1 or no £1. Feel free to post after the summer. I strongly suggest you check both your dates of travel here http://www.nationalrail.co.uk/service_disruptions/currentAndFuture.aspx?TravelDate=&TOC= for example 25-27th (Sat-Mon) August No trains to / from London Euston from Saturday 25 to Monday 27 August
if the trains actually worked, this would be a great deal. could you imagine being stuck on a train for 3 hours with no aircon in this heat. it will happen...
Ummmm check your facts before making sweeping statements - only free if they are under 11 and they may need a kids 5-10 zip oyster card for some national rail journeys in London to travel free. Link below explains fully - https://tfl.gov.uk/fares-and-payments/travel-for-under-18s/travelling-with-children
Great price if you live in the area.