When I first came to BYU-Idaho, there was room in the budget for me to have a couple of hours of "lab" time for TAs. Students could come in and get questions answered, work on things, and meet with me or the TA to go over grades. When the TA hours shifted, I moved things around to make sure that students still had access to this resource--and what's more, I began to require that students attend once every three weeks or so. A number of students complained. "Why do you make us do this?!" All they have to do is show up, take a picture, and they can go--and they can meet with me in office hours or schedule outside time with a TA if they prefer too.
And what's funny? A lot of them end up sticking around and set a schedule to come into lab each week. Students really appreciate it, and grades are high.