Robert designed the 50 star flag while in high school. The teacher gave him a B- for lack of originality. The teacher agreed to raise his grade if he was able to have his design adopted as the new flag.
This happened in 1959 and it was his design that we know today.

He also has a 51 star flag ready and waiting, in case we adopt a new state.

"Robert G. (Bob) Heft (born in Saginaw, Michigan in 1941) is a designer of the 50-star flag, and one of the proposed designs for a 51-star flag for the United States of America. He spent his childhood in Lancaster, Ohio, where he created the flag as a school project.He designed the current U.S. flag in 1958 while living with his grandparents. He was 17 years old at the time and did the flag design as a class project. He unstitched the blue field from a family 48-star flag, sewed in a new field, and used iron-on white fabric to add 100 hand-cut stars, 50 on each side of the blue canton.1He originally received a B- for the project. After discussing the grade with his high school teacher, Stanley Pratt, it was agreed that if the flag was accepted by Congress, the grade would be reconsidered. Heft's flag design was chosen and adopted by presidential proclamation after Alaska and before Hawaii was admitted into the union in 1959. According to Heft, his teacher did keep to their agreement and changed his grade to an A for the project Heft has also stated he has copyrighted designs for 51- through 60-star American flags.2When Alaska and Hawaii were being considered for Statehood, more than 1,500 designs were spontaneously submitted to President Dwight D. Eisenhower by Americans. Although some of them were 49-star versions, the vast majority were 50-star proposals. At least three, and probably more, of these designs were identical to the present design of the 50-star flag. These designs are in the Eisenhower Presidential Archives in Abilene, Kansas. Only a small fraction of them have ever been published.
After graduating from college, Heft became a high school teacher and also served as mayor of Napoleon, Ohio for 28 years. After retiring from teaching, he currently is a motivational speaker.." (information obtain from http://en.wikipedia.org/wiki/Robert_G._Heft)