i have a kenmore dryer that just will not heat i have checked continuity with a multimeter from the heating elements all are coming up with great continuity the only one that's not is the thermister this goes about half way on my multimeter so i bought a new one and the new one is doing the same thing so im guessing this is not the problem . i took out the thermostat to clean it i shook it and it made a rattling noise could this be the problem?i have also checked the outlet and theres 240vs coming in so no problems there . someone please help im racking my brains but cant come up with anything

[COLOR="DarkRed"]the only one that's not is the thermister this goes about half way on my multimeter[/COLOR]
The thermistor should read about 12,000 ohms at room temperature

[COLOR="DarkRed"]i took out the thermostat to clean it i shook it and it made a rattling noise could this be the problem?[/COLOR]
Yes it could, it should not rattle. I am assuming you are talking about the hi-limit thermostat (tenth item in the parts listing).
Could be it just blew but also could be that it was switching on/off when it blew. It should only switch off/on if you have a problem elsewhere in the unit as it is a safety device with the thermal cut-off (first item in the parts listing) as a back up.

Pull the heater relay and check that the contacts are open (common to normally open) (the two large red wires), could be the contacts are welded together.

When/if you get it all back together and have heat run a low temperature cycle to make sure the the unit is giving low heat. If not then you still have a problem.

[COLOR="DarkRed"]i have also checked the outlet and theres 240vs coming in so no problems there .[/COLOR]
As RoboJoe said check the terminal strip voltage it could be a burned off wire or a bad line cord.

You have checked L1 to L2 for 240 volts at the plug.
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
[COLOR="Red"]Be careful as 240 volts is lethal !!! [/COLOR]

At the top of my list would be your rattling hi-limit thermostat.
Also check that the thermal cut-off is OK (0 ohms).