Create a calender on the bulletin board. Write a different prize on the back of a sticky note and place one over each of the remaining school days on the calendar. Prizes could include an inexpensive object or a special privilege. Each day, have a different student remove a sticky note and claim the prize. Ensure that all of the students have a chance to uncover a number.
Instead of counting down the remaining days of school with numbers, consider using letters of the alphabet for the last 26 days. For each letter, create a theme for the day. For example, have the children bring something from home that starts with the letter "A" or wear something with a zipper on "Z" day. For the letter "X," you could have the students draw a picture of a xylophone. Place the letters on the bulletin board. Remove each letter as the days progress.
During the last days of school, have the students bring in photos or pictures that show their plans for summer. For example, if a student plans to visit the beach, have her bring in a picture of a beach; if a student plans to visit his grandparents, have him bring in a picture of him with his grandparents. Each day, have a student place her picture on the board and discuss what she hopes to do over the summer.
Have the students draw and cut out an insect avatar of themselves, such as a bee or a butterfly, and write their names on them. On the left side of the bulletin board, place the outline of a large box representing the students' current grade level, such as second grade. On the far right, place another outlined box representing the grade for the following year, such as third grade. Draw lines in between the two boxes and divide them into the number of school days left. Each day, have the students move their avatars to the next section away from box one and toward box two, so that on the final day of school, all the avatars will be in the second box.