We've used the Scratch-Art brand Penholders on two go-rounds now and the semester isn't even through. I'm so pleased to say that they are holding up beautifully. In previous years we were using a different kind of pen holder and they were TERRIBLE. (Sadly, they were Dick Blick brand and usually they are good but not in this case.) They were constantly breaking and/or cracking at the end where the blade was inserted and they would usually not last through a full project before we would have to just through them out and open new packages of handles altogether.
These Scratch-art brand ones though? THEY ARE AWESOME!!!! They are sturdy and well designed so that they are both comfortable to hold and easy to manipulate. They are also very economical for the budget and if you order them from Blick you can get bulk discounting! The only drawback I've found so far is that once you put a tip in, they are difficulty and possibly dangerous to get out (you could slice your hand if you aren't careful) so just expect that once you commit the handle to once type of tip, that's it and you can't change it up.
Just a note, I'm not being paid or compensated in any way for any product reviews I've offered thus far. I review and offer praises for these products because I've seen a real lack of comprehensive product reviews out there for things that are commonly used in the art classroom and I hope that I am offering up something that can help others better manage their supplies budgets. One of my greatest frustrations as an artist and art educator is the challenge I've had of ordering something I thought would be useful only to find out it was a waste once I tried to use it. True artists honestly can make beautiful art work out of just about anything but good and solid materials and tools sure do make the process a whole lot more enjoyable during the creative process.