You need Fuel/Air, Spark & Compression for a 2 stroke to run.. remove any of these and they won't..
You have spark. Are you getting fuel? Don't just assume you are.. Pull the carb and give it a good cleaning, make sure all the jets and whatnot are clean and clear.
Are the reeds in good shape? While you have the carb off soaking, pull the reed cage and check them for cracks and that they seat on the cage. If there are cracks or they sit off of the cage, even a little, replace them.
Do a compression check with a compression gauge. Make sure it's within spec. If not, its time to do a top end.
It could also be that you don't have enough of a spark.. Yeah, it looks good when you have the plug out of the head, but when it's in the head, it's not enough to fire the bike.
Hope this helps..