The pilot was practicing touch and go and full stop landings. On the third landing attempt the pilot had about 25 degrees flaps selected because he recognized he was higher and closer to the runway than normal. He felt he was stabilized on final at about 85 knots by mid-final. He flared and touched down lightly, but the airplane bounced slightly and floated one to two feet above the runway. The pilot added back pressure and the airplane suddenly touched down. The pilot added power and a porpoise developed. The propeller struck the runway and the nose gear collapsed, bending the firewall. The airplane stopped on the runway. The pilot did not report any airplane malfunctions prior to the accident.