She should be able to buy tickets at the box office for Grease, particularly for a weekday show at this time. If she has the time, she should go to the TKTS located in the Marriot Marquis and she can get tickets for the same day to many shows at a very discounted price.

There is also student rush tickets but they are harder to get for some shows.

Tell her to have a great time - going to rain a bit here today, but should be nice (60s during the day, 50s at night) for the rest of the week, maybe some rain Saturday.

NYC is a great place to visit or live