Can't you photograph the school compound at sunset/sunrise from an opposite HDB, print out a nice big photo, frame it and present it to the Principal? Just make sure it's a cheery inspirational photo, not dark and gloomy la. Which other CCA can give an advertisment 24/7. NPCC cadet guarding the door or potted plants from the Gardening Club maybe?
Accept the fact the photography club is there to support other CCAs. Since you're not getting real support you should make the case that you all do good work and are indispensable to the school. Go through each CCA and shoot a good portfolio of images. Approach their teacher-in-charge, share the pics and get their support for you. If they can tell the Principal "Hey the Photography Club shot these great pictures!", "I want to use them on so-and-so event" Isn't that free advertisement also. When they put up the photographs in the website, ask the webmaster to credit the club. It's just 1 small line per page, I'm sure he won't mind.
Experimenting with smoke and water drops are fine to attract the club members but they should know the current situation isn't to their advantage. Hiding away in the clubroom is not going to get the affirmation you need from the school board. Be seen and recognised! You guys have Tees now right, all the better no? As long as you all are active, not hiding somewhere doing your own things, people can see you're hardworkers. Have a plan, have a schedule. If you must, meet with your teacher-in-charge and Vice-Principal/Principal. Say this is the Club's direction, we have a schedule and these are the activities we're implementing. Stress you have no funding, but will make results nonetheless. Then next time lament, this is good but you'll be better with funding. They are like some parents lor, if you can give concrete reason for spending they will allow for it. Get serious with the adults and they're forced to take notice. Show who's in charge.
The pictures do not have to be record shots. All CCAs have their equipment, uniforms, etc. The school itself has so many other goodies. The science labs, design & technology workshop? Play dress up or something, get the teachers involved. Learn composition and lighting that way. No flash, use continous light, use natural light. 50+ pple in the club someone can surely do something. So much manpower, use them first. If they don't want to do or play punk then kick them off the club. Have your core team send them out for mini-projects or something. Tell them you need lights to shoot the science lab but have no money for flash, go do research how to solve the problem. Solve time, location and resources. No camera to shoot does not mean no brain to imagine, or eye to see. If they prepare everything, maybe the incentive is they get to do the shoot, one of you to supervise. The result may be campy or unrealistic, it doesn't matter. That's the whole photographic process to me. Developing film or learning DoF is a very small part.
Work triple hard first, when you get the funding and all, then enjoy the fruits of labour and shoot whatever you like. Cheers and good luck!