have each member write their parts by themselves. you can start with a cool riff, then add a beat to it. put some chords under it, add a bassline. then write lyrics for it. kinda build it up instead of just jamming you know?
just have everyone kind of write some of there own stuff outside of when you jam. Thats the way my band does it. Someone starts it off with somethen they wrote then we all add pieces to it and end up with a song. It seems to be really effective, we can get 1-2 songs done everytime we jam
thats how i write, whenever i think of some words or a beat, i write it down, then later come back and see if i can add on to it. its worked for over 30 songs so far.
dont look at writing songs as a chore. Have fun doing it.
I find its better recording the songs then showing them to the band, I've done that for a few songs already. It makes it so, theyre much more likely to play their parts closer to the way u want the song to sound. if you jam something and the other players write their parts to it, and you're unhappy with it, theyl get more annoyed then if you just wrote their parts for them. But still, always be open to opinions and suggestions by the other members.