I have applied for a coupe of people recently (for Thomsonfly flights), hopefuly if one of them was you I have sent you an email - if not then do 'shout at me'. It is always advisable to pack the charity items seperately, no need to put it in a suit case, you can just use really light weight canvas or similar bags, some people use those thin white/blue/pink plastic bags which you can get from the markets? or maybe the pound shop, just put a bit of tape round them and you should be fine...
I've stopped using suitcases at all now as most suitcases themselves weigh a few KG's some as much as 4 or 5kg!! It reall makes a dent in the weigh allowance.
Clothing is good, before Christmas small presents would be great (small toy cars, footballs, tennis balls, skipping ropes, dolls, 'punch balloon are great, hair bobbles (nice ones), fake jewellery, nail polish (probably cheaper in India)), last year we gave out 1000 wrapped presents, would be nice to do the same this year. Other UK items which are good are children's vitamins, bathroom items, we've actually got a Wii now, so some games people have got bored of would be good... anything is good (as long as it's related to children).
Crayons, Pencils felt tips and stationary is probably cheaper (for better quality) in Goa itself, unless you have a cheap supplier in the UK.
Thanks