Sunnyvale school district just completed construction on the schools there, but new construction in the area is not in the price range you specified. You'll need at least $450k to look there.
Personally, for the money I would entertain Sachse, which is north of Rowlett. It is close to Firewheel shopping, easy access to Bush for commuting and has some excellent value for money on newer construction. There are currently 3 newer homes there that seem to meet your criteria. Sachse High School is a recognized school in a suburban neighborhood.
Rowlett also has 1 newer home that seems to fit. Easy access to I-30 and Bush, and the DART light rail will open soon. Rowlett High School is also recognized.
Rockwall seems to have 1 that fits. Access to I-30 and Bush is a little more complicated, but shopping is great and dining couldn't be better. Rockwall High School is recognized.
Frisco has 6 high schools, 5 recognized and 1 exemplary. Access to the Dallas North Tollway is easy and shopping around Frisco is outstanding. Currently 5 homes seem to meet your criteria for newer construction and so on.
Both Plano and Allen are possibilities, too, each having 1 home currently and excellent schools and transportation.
I found all these on our website http://www.Rowlett-Realty.com which we're in the process of bringing up to standards. You can get a free personalized report emailed to you concerning prices and trends in a neighborhood plus local information about it at http://www.DallasHomeValueReport.info
I looked at your questions and did a little research for you. If you are looking for a new home in Sunnyvale between $250K and $275K you won't find it at this time. Sunnyvale has only 18 homes actively for sale right now. They range in price from $209,000 to $3,700,000. Among these 18 homes there is only one new construction home. It is for sale at $499,000. In Sunnyvale most of the homes are on larger lots. Of the 18 homes for sale 10 of them are on lots larger than a half acre. It is a very beautiful area of the Metroplex.
Meanwhile in Frisco you will find 100's of homes for sale. It is a much larger area. Yet, there are only 13 new construction homes in the zip code you requested. They vary in price from $157,000 to $258,950.00. So there is still only one in the range you specified. You will find that both areas have great homes in the price range but, most are pre-owned. If you would like further information on these homes please feel free to contact me at 972-815-7325. Thanks for asking for help. Judy Vessels