Nothing brings a history alive more than actually seeing and experiencing the locations studied in school, and the entire family will benefit from foreign travel if they take the time to thoroughly plan the trip. In addition to the obvious, details that may be overlooked are important to truly experience the culture of other lands. First and foremost, the family should learn about the culture of the country. For example, when traveling to Paris, the family that really wishes to fraternize with Parisians will take the time to learn key phrases. The French are very proud of their heritage and look on most Americans as being too arrogant to learn their language. Learning how to greet shop keepers and restaurant owners in French and demonstrating a true desire to use French will endear your family to them, and they will be thrilled when your children also demonstrate an effort to do the same. Americans who return from Paris stating they had been treated rudely no doubt made no effort to speak French. The French do not expect perfection but just appreciate the effort.
Parisian women do not wear shorts or jeans in the city, and although the "liberated" women of the States may take issue with this point, it is a much more comfortable feeling to walk about in appropriate dress. French men also do not wear shorts on the streets of Paris, although southern France is much more lax in the summer. Casual slacks and shirts for men and summer dresses for women will be comfortable while allowing you to fit in.
Prior to leaving, it is imperative that you change your money into Euros. There are banks in most areas that will do this in advance, and you will not only get a better rate of exchange, but you will not be stranded with no money should your plane be delayed for some reason, and you find most places that accept Visas are closed.
Families should register with the state department at : https://travelregistration.state.gov/ prior to departure in the event of any type of emergency and give itineraries to family members with phone numbers. In addition, call your insurance carrier for the overseas number in case of illness or accident since this number may not be available overseas. General knowledge of local laws is another necessity and can be discovered at http://www.travel.state.gov/travel/cis_pa_tw/cis/cis_1765.html