So there's this canal that has about 50% weeds 50% water and its about 6 feet deep in the middle, and there are sometimes 5-10 4-7 lb bass schooling, and they wont bite. What lure/line/technique should I use?  

What kinda weeds???

If they are chasing bait fish you could try to match the size of bait fish there chasing with a crankbait, inline spinner, etc...

Saturate fish that water buddy, I mean make a day of it.... 7" T rigged strait tail worm...

You seen them, now you gotta slow down and soak that worm.... You do this? You will catch fish. Also get yourself a large, size RAPALA topwater ( Balsa) Rubberband those hooks against the body... Fish it at first and last light, or shade... And catch Bass.... Done all I recommended and caught LMB to 10 pounds....

Now, go catch those nice fish.... You can thank me later!!

Serious, fish that water 10 hrs. A day... Get Bit...

Drop a bait in there easy that will make them angry, like a zoom lizard or a creature bait.  Fish it slow and see what happens.

Nightcrawlers 

Nightcrawlers

Hey that's cheating! He said lures... Lol

Hey that's cheating! He said lures... Lol

 

 

Alright.... lure them in with a finesse worm then drop a nightcrawler on its nose. 

Floating swimbait. Keep pulling it past them with different retrieves until you get some interest from a fish. Chances are if you can get one to look you'll soon have the whole school moving towards your bait, then it's just a matter of getting one to commit. Even if they're mostly inactive, a big, easy meal is hard for a fish to pass up sometimes. 

http://www.bassresource.com/bass-fishing-forums/topic/11664-warning-you-might-get-your-arm-broke/