My family spent Christmas 1997 in New York. I recently found the letters that my then seven-year-old’s classmates wrote to him
The main conceptual idea behind the text snippets you've provided is the juxtaposition of ordinary life and the significance of Christmas.
The author highlights this contrast by mentioning everyday activities like playing tennis amidst the holiday season. This is further emphasized by mentioning relatable news items like "Our class is on the internet" and "Mary McAleese is the president."
The text suggests that Christmas, despite its idealized image, is also experienced as a time for normal, everyday occurrences.