Job hunting is a tricky monster to tame

So, it seems that timing is of great importance when it comes to the job hunt. Here's the deal. Last week, I interviewed for two positions: one as a middle school social worker in Grand Prairie, the other as a Rehab Specialist at Millwood, Center for Chemical Dependency and Mental Health, here in Arlington. Both positions said they would get back to me by the end of the week, as in tomorrow. I now also have an interview set up with the Boys and Girls Club for tomorrow at 10 am for an LMSW in the Prevention Services Department, where I would be doing therapy with kids and their families and home/school visits. Another piece of important information is my interest in these positions. I am most interested in the middle school positions, then the Boys and Girls Club, then Millwood. So, here is my dilemma. Millwood offered me the position yesterday and I told them I was interested, but that I was waiting on another offer also. She said that was fine, but she needed an answer by Friday. So, I should hear from the school by Friday. So, if I get the school job, there is no problem. I accept that position and decline Millwood's offer by her deadline. Now, if I don't get the school job, there is a small problem with timing. I would like to interview with the Boys and Girls Club and wait to hear from them, but millwood needs an answer by Friday. So, I was thinking I could accept the Millwood job, but tell her I couldn't start for a week and that gives me enough time to hear back from the boys and girls club. If I get the Boys and Girls Club job, I could then decline the millwood position, but no matter what the Millwood position would be there to fall back on. I think this idea would work, but it is very mean and slightly unprofessional. I have never done it before, but people tell me it happens often in the job hunting world. Well, any advice would be greatly appreciated.

Well, two pieces of good news in all this. One, no matter which job I get, I will have a full time job very soon. YEAH!! Also, Michael and I are going to see Sarah Mclachlan in concert tonight!!! YEAH FOR THAT!!