Time changes, but not the horn beginners' universal will to practice just C, and only C major scale every day!
Now, that every student is born already logged to facebook and with their smartphone batteries fully charged, nothing better than using the "new technologies"
Well... SMS is not quite new as the first SMS was sent already 22 years ago!

I've implemented this idea with some of my students and it consists on setting up a google calendar to send daily SMS for free informing which scale to practice every day. This way, students can receive the scale, memorize the relation between major and minor scales and if they decide not to practice, at least the get the SMS for making them feel guilty...
The calendar can be accessed on the following formats XMLICAL ou HTML and subscriber to a gmail account.
After subscribing, you only need to open the "calendar configurations" then the "reminders and notifications panel" and select how you would like to be informed. If you set up SMS reception, google will sent you a free SMS every day!
Now there's no more excuses... if the students will not go to the scale, then the scale must arrive by SMS to the student!

UPDATE: Google stopped sending SMS messages, but you can still use this calendar on your mobile phone.