Unlike in other Access views (like Report and Form), you can't format individual fields or entries differently from the rest. You can choose a different font for the display, but it automatically applies to all the text in the table, including the column headings.
Font changes you make in Datasheet view will not appear in your reports, queries, or forms; they're for Datasheet view only.
Why Would I Change the Table Font?
You might want to make the font smaller so you can see more of the field contents on-screen without bothering to adjust column width. Or you might make the font larger so you can see the table more clearly.
To choose a different font, follow these steps:
Select Format, Font. The Font dialog box appears ...