http://www.jimmys-adventures.net/hiking-umbrellas/

Going hiking… what should I pack?
Well, since the teacher basically force us all to go I have no choice. :/ I have asthma so I’ll be taking my med., what food should I pack? I’ll also be taking a small pocket knife, umbrella, raincoat, towel and lots of water. We have to wear our cadet uniform, it’s dark green and a bit heavy.
If your teacher (leader?) is competent with running a hike they will have a basic equipment list available to give you (when I say competent, they might be brilliant at walking, but rubbish at the organisation such as letting you know what you need). So depending on where you are going and the length of the walk they can advise you best.
Apart from that the basics you need will be:
Bag to carry your stuff in – backpack is best
Bottle of water – can be a ‘walking’ water bottle of a couple of empty coke bottles (about 1 litre in total)(water is better than fizzy drink, though soft diluting juice is OK too)
Lunch – sandwiches are good, cake, chocolate bar, and maybe an apple are good. Try to pack these in a plastic box since you are more likely to take this home and not drop litter
Bag of sweets to eat as you go
Asthma medication
Raincoat
Long sleeved top
Hat and gloves (if you are going up high hills or mountains, sun hat if it going to be sunny)
Sunny – then sun block
A sense of humour can help – being able to chat and tell jokes all day long
I would ignore the knife (no need for one) and umbrella – it will get caught and ripped by hedges and trees, and towel – it rains, put your jacket hood up
If you can try to avoid wearing denim as well
This link has a few more ideas:
http://www.kirklevingtonexplorerscouts.org.uk/k_wkit1.htm
Nanta-hail-a