Can a blocked extra point try be recovered by the kicking team for a 2 point conversion?

Answer 1

In high school, the moment the ball is kicked on a try, the play is dead.

In NCAA, if the ball touches the endzone or a player in the endzone, it is a touchback.

In all other levels and situations, it works identical to a field goal or punt. It is called a 'scrimmage kick', and if the ball is blocked from behind the line of scrimmage, and offensive player may take possession and run in for a 2-pt conversion. If the kick sails beyond the line of scrimmage, the defense (or 'receiving team', since the kick obviously doesn't make it through the back of the endzone) has to touch the ball. However, attempted blocks near the line of scrimmage are ignored when considering touching by the defense.

For more info: if the kicking team touches the ball after the try doesn't make it, it is like when a punt is touched by the kicking team. Regardless of what happens after the touch, the receiving team has the option to take possession at the 'first touching' spot (this is why punt units fully 'possess' the football instead of touching it).