In NFL history, there have been many games that got off to incredibly fast starts where teams scored lots of points in the first half. There are several classic games where fans who witnessed them will probably never forget.
The most points by any team in the first half ever happened on October 2nd, 1983 in a game between the Tampa Bay Buccaneers and the Green Bay Packers. In the first half alone, Green Bay scored 49 points which still stands as the most points in the first half by an NFL team in history, as of 2015. The game ended up with a score of 55-14 in favor of the Packers.
The second most points in NFL history by one team in the first half happened September 18th, 1966 in a game between the Buffalo Bills and the Miami Dolphins. The Bills scored 48 points in the first half and the game ended with a score of 58-24 in favor of Buffalo. The most points combined by both teams in the first half of an NFL game happened on December 22nd, 1963 in a game between the Oakland Raiders and the Houston Oilers. The score at halftime was 35-35, and the close game ended up in favor of Oakland 52-49.