Furnace problem question...?

Have a Carrier furnace about 10 years old. Started acting goofy a few days ago when we noticed that the house was cooler than it should be. If you turn the thermostat temperature up to activate the heat nothing happens... Go downstairs and flip the power switch for the furnace off then on the blower starts...minute later gas ignites...furnace heats up... flame goes off... blower cools down furnace and it shuts off... but flame never reignites again. And it won`t until I flip the switch again to let it go through that single cycle again. Any educated advice out there would be appreciated...Thanks in advance!