damn integra

i have a 94 integra and i've been having problems with it lately, when i turn the ignition on it makes a clicking noise and doesn't want to start so i get the battery boosted cause that's what i assume it is. so i'm driving for a couple of weeks or so and one day i go to the store to pick something up and i'm in there for like 20 mins come out and my car won't start again.....same clicking noise. i get it boosted again but this time i bring it home so i can hook it up to a battery recharger, it says the battery is half full but i recharge it anyway for about a day until it says its full, then i try to start it up and it won't anybody know what the problem could be, any help or advice would be great!!!

sorry this is soooo long!!

thanks