Cook the macaroni by following the directions on the macaroni package or do the following: Add macaroni to four quarts of boiling water with 2 tsp. salt. Keep stirring and cook for 20 minutes. Drain water and discard (use colander).
Hard boil the 3 eggs while your macaroni is cooking. Rinse cooked macaroni with cold water.
In a bowl, add the cooked macaroni, hard boiled eggs (cut up), chopped celery, chopped celery heart, mayo, mustard, sugar, and celery seed. Stir everything with a spoon. Refrigerate before serving.