VINEYARD HAVEN, Massachusetts (AP) -- Summer reading and a bit of golf. That says vacation for many Americans. And briefings on the economy and national security if you're the president.

Barack Obama began the first full day of his Martha's Vineyard vacation on Friday by taking his daughters book shopping, then hitting the golf links at a private course.

The White House was at pains to point out he also was briefed by aides on national and international issues.

At the Bunch of Grapes bookstore, Obama was greeted by shouts of ``2012'' and ``Four More Years.'' Dressed casually in jeans and an untucked blue polo shirt, he introduced his daughters to patrons before setting off in search of vacation reading. The girls, meanwhile, shopped with a purpose.

``They've got to buy some books,'' Obama said of Malia, 13, and Sasha, 10, adding that one of them had a school assignment.

One woman, Terry Wilson, 63, told the president: ``Please don't forget the teachers.'' Obama replied that he loves teachers. ``How could I forget them?'' he said.

At the end of the 15-minute shopping trip, Obama was seen holding five or six books, including ``Brave New World,'' Aldous Huxley's futuristic classic, and ``The Bayou Trilogy,'' a crime novel by Daniel Woodrell set in Louisiana swampland.

Obama emerged to cheers from well-wishers who were kept behind yellow police tape, then climbed into his sport utility vehicle and rode back to his vacation compound to drop off the girls before being driven to Vineyard Golf Club in Edgartown. Aides said his afternoon foursome included longtime Chicago friend Eric Whitaker and two White House staffers.

Several Republican presidential candidates have criticized Obama for coming to this upscale island resort off the coast of Massachusetts at a time of economic uncertainty across the country.

The 10-day stay on Martha's Vineyard is Obama's third straight summer on the island off Cape Cod, and his visit to the Bunch of Grapes was a reprise of how he started last year's vacation. Once again, it was a father-and-daughters outing, with first lady Michelle Obama elsewhere on the island.

Inside the bookstore, once Malia and Sasha had picked out books, Obama went to the cashier to pay but was heard disagreeing with the $32 price he was quoted, which seemed low for the size of his stack. He later paid by credit card, telling the cashiers that he uses it only about three times a year.

``We're counting on you!'' one patron yelled as Obama left the store.

Later, Obama and the first lady had dinner at the Beach Plum Inn overlooking Menemsha Harbor, eating as the sun set over the lobster boats and motor yachts. They spent an hour and a half at the inn before returning to Blue Heron Farm. The Obamas dined with friends at the restaurant last year. This year it was just the two of them.

The White House defends Obama's desire for time to recharge and spend time with his family before the new school year begins. Officials also say the president is never really on vacation.