Concord Coach Lines operates a bus from Boston to Scarborough hourly. Tickets cost $20 - $28 and the journey takes 1 h 50 min. Alternatively, Amtrak operates a train from Boston to Scarborough 5 times a day. Tickets cost $30 - $70 and the journey takes 2 h 30 min.
From Logan Airport bus to Portland, ME then taxi to Scarborough. 1 h 59 min $58. From Boston North Station Amtrak train to Portland Transportation Center Amtrak then taxi to Scarborough. 2 h 39 min $80. From Boston drive to Scarborough. 1 h 51 min $12.