Well you just missed "Headlights for Lighthouse" last weekend, the tour of several of the lights.
Since you staying in Hyannis, you are kind of in the middle of all the lights. I would head out early one morning to Provincetown first. You can drive through town until you get close to the rather long breakwater (.7 of a mile long). Find a place to park, wear some comfortable shoes and hope the tide is falling or low. Part of the breakwater may be underwater at high tide. If you walk the entire breakwater, you will see Wood End Light 1/2 mile from the end of the breakwater and Long Point about a mile in the other direction. You could drive up to Race Point's Ranger Station and inquire if any vans will be available to take you out to Race Point Light. It's 2 miles from the parking area and really too far to walk in loose sand.
As you head back for Hyannis on rte 6 you can stop and see Highland Light, then Nauset Light and the 3-Sisters, then on to rte 28 and Chatham Light, then over to West Dennis and the Lighthouse Inn to see the old Bass River Light. The next day you can go over to Falmouth/Woods Hole and see Nobska Light.
Those are the easiest lights to find and open to the public as far as driving up to them and then walking.
Bob