my suggestion is ask the person in charge of the home. i often hear how some charity homes resell stuff for money... and the mismanagement of funds. so... buy items but not a lot in bulk... so they can't resell.
for children homes, the caretaker likes people to spend time with the kids to inspire them to have a bright future... encourage them to study degree and bla bla. play sports...
elderly home... spend time with them. listen to their stories.
others... some ngos need administration help so if u all can provide assistance more than one day, then u can ask what kind of administration u can help out. sometimes it's just writing into companies for sponsorship/fundraising...
try pandawas academy, it's in ampang. it's school teaching the refugee children. sometimes they need books, stationery and the like. they have a fb page. u can check out there.
cleaning.... i have never done that but u can ask if they need such help.
I will contact them and see how we can help ..
Really thanks alot, at least I know where to start off.