I think Broch's suggestion is a good one "stealth teaching", the question is in what order? Tarp. knife, fire, making tea. ???
Boonies Outdoor Same kit different branding £37.45
alternatively doing a pick an mix of equivalents
Ground-sheet, tin mug, tent pegs | Poundland | £3
Camo tarp 6x4 feet | Ebay | £2.95
Canvas haversack ,, £6.45
15m jute rope ,, £5.89
Bush mallet is easy enough to make if you think they need it... that comes to £18.29 so far including postage
Shemagh £3.38
Camo face paint £2.99
Poundland COB headtorch & batteries for a week £2
kids 6x30 binoculars £4-5
Camo netting 3x5 feet £4
Optional xtra:
Cardboard shipping boxes 10"x7"x3" pack of five £7.50 --- for DIY kids ration packs (fill as needed with coke, crisps, chocolate etc)