I doubt anyone here has heard of anyone being deported for such activities. The only people that get deported for these things are those that get active in politics...and it isn't hard to make that jump (Charity+Human Rights=Politics). You will almost certainly get away with it. If you are really that worried about it (and about doing the right thing) I would suggest you get the proper visa. If you can't afford, or don't have the motivation, to leave and get the proper visa then you are just going to have to risk it. I could not find a single instance online of a tourist getting busted for working with charities...but that doesn't mean you can't be the first they want to make an example out of if you unintentionally step on the wrong toes, which isn't hard to do in the Philippines. Nobody here should suggest you do anything illegal (such as working on a tourist visa). Can you get away with it? Most likely, but that doesn't make it right. It is on you to evaluate the risk vs reward and if you want to do the right thing or not.