Our bedrooms all have arc fault breakers... when you plug a vacumn cleaner into the wall outlets in any of the bedrooms, the breakers kick out and have to be re-set... they are 15 amp breakers... what can I do?

Could be the vacuum has a problem, Have you tried to plug in anything else?

If I was to guess, These were recently added or recepticles are now just being used.
They can't simply be swaped like a regular breaker.
If neutral is shared with another circuit. It will trip.
May need to pull a neutral from panel to where the circuits separate.

What is the load of the vacuum in amps, watts or horsepower? This info can be found on the nameplate of the appliance. Could be the vacuum is adding too much to the circuit so the load of the vacuum and the other load on the circuit is causing an overload.

Or it can be the brushes in the vacuum motor are worn and causing arcing, which is exactly what will affect an Arc Fault breaker