From my perspective, the issue with half-Shabbos is how it can be prevented. In a lecture that spoke to this issue, Rabbi Jonathan Rosenblatt of Riverdale spoke about the need to re-capture Shabbat for our children (and students). In a nutshell, if Shabbat is all about the don'ts and can'ts and shouldn'ts then we are conveying to our children that Shabbat is a day of restrictions, and of course that natural teenage need to somehow rebel will see Shabbat as an easy target. Religion is one of the prime areas in which kids express their individuality/rebelliousness, as there is not much that their parents can do to stop them short of punishment - and every parent and teacher knows that one has to be careful with a kid who is threatening to go "off the derech." Kids tend to know that parents are afraid that one infraction is just the first step to full-scale abandonment of religion, and thus for those who are so inclined, religion is quite a weapon in their struggles with parental or other authority.
However, if we can make Shabbat into a positive day, we may be able to get ahead of this problem. If we approach Shabbat, both at home in and the classroom, as a wonderful opportunity for rest, for coming together as a family (something that may be a rarity for many families during the week), for hanging out with friends, and so on, then we may be able to decrease the need to violate Shabbat as an act of rebellion - why would someone want to militate against something that is so positive?
[Obviously, if half-Shabbos is more a function of addiction to texting, then the journey may be a different one. I suppose that is for a different post.]
This comes to my mind as one and the same with how we approach Pesach. Full disclosure - I love Pesach. I love the seder, I love being with family and perpetuating long-standing traditions, I love the fact that it is a nice vacation during a beautiful time of year. Fuller disclosure - some years I make Pesach and some years I do not. When I do make Pesach, I am involved in every aspect of it, from cooking to cleaning, including lifting all sorts of pieces of furniture in search of Lord-only-knows-what.
That being said, few things grate on my ears more than hearing people complain in front of kids about the stress and labor involved of making Pesach. No question - there is much stress and much labor. We may very likely be cleaning more than we have to (consult your Local Orthodox Rabbi on that one), and keeping up with which products are and are not acceptable can be quite a challenge. Cooking for a cast of thousands with limited ingredients in the two days after the kitchen is kashered is a task that far exceeds making Yom Tov any other time during the year.
But what do our kids hear? Do they hear about the wonder of the holiday? Do they develop a sense of excitement and anticipation coming into it? When they are younger, they surely do, as they come to the seder armed with colorful projects and joyful songs and whatever else they learn in early childhood. But as our children and students grow up and become more sensitive to the subtle messages that we convey, are we aware of the messages that we are sending them? As with Shabbat, are we communicating that we are looking forward to all that this day has to offer, and we hope that they will as well, or are we presenting the holidays as days on which to rest from the burden of preparing for the holidays?