Jeremy,
You can do this to a certain extent, if the checkbox fits entirely in the
cell. Ctrl-Click it, and use the handles to make it fit. The checkbox will
be copied when the cell is copied, etc. Also, right-click it, Format
Control - Properties. Here you'll probably want Move but don't size with
cells. Any cell contents will be under the checkbox, and thus obscured by
it, so you may have to mess with things to position the cell contents,
depending on what kind of stuff will be in the cell, and if it will vary.
YOu may find it simpler to put the checkbox in an adjacent cell, by itself.
Can't say more not knowing more specifics about your situation.