Festoon the celebration area with paper streamers and posters in the basketball team's colors and featuring images of the mascot. Add drawings of mortar boards to the head of the mascots in the pictures to allude to the seniors you are honoring that night. Do not forget a sign saying, "Congratulations Seniors!"
For a more formal Senior Night event, decorate tables with flowers, but combine the flowers with a basketball theme. Wrap basketball nets around pots of flowers with a small basketball placed in the middle of the floral arrangement. Use each of these as a centerpiece for the tables at a formal senior night banquet. Hang orange balloons with black lines resembling the seams of basketballs drawn on them from the chairs at the end of each of the tables.
Create life-sized, stand-up cardboard cutouts of each of the seniors on the team from photographs and arrange them in rows along the aisle leading to the door. In lieu of this, hang framed photographs from the walls of all the senior players. At the end of Senior Night, the students get to take home their photograph or cutout. Create a banner to hang over the photographs saying, "Congratulations Senior __!" with your school name or mascot in the blank.
Make each of the seniors on the basketball team a star for the night. Attach a small photograph of each player onto a basketball cutout and tape both to a gold star. Continue the star theme with the other decorations by stamping paper streamers with a star-shaped stamp. Hang the stars from the ceiling with streamers in the school's colors or in gold and silver to reflect the ceremony of the night.