Lots of curlies wash more often than once or twice a week, especially if they are using styling products. Very few can get away with less than that. CO-washing is very good for your hair and helps to keep it hydrated and moisturized! There are lots of tips on this site:
http://www.livecurlylivefree.com/curl%20care.htm
You could try "Plopping" her hair and scrunching out excess moisture with a T-shirt but it takes a long time to air dry. How about using the blowdryer on LOW setting? You may only need to do that for 15 mins. or less. The stronger the curl pattern the less you would need to wash, she might be able to get away with washing on the weekend and spritzing with Lavender Water or Conditioner/Water mix during the week if she's not using a lot of stylers.