M.M.
Ah....the 100 day project! When my dtr was in kindergarten we made a sunflower on study cardboard with 10 petals. On each petal we hot glued 10 lemon head candies. It was large and bright! It was an enjoyable project that she still talks about.
I remember the teacher sharing the various projects she had seen over the years. One that stuck with me was a Super Bowl themed football grid using teddy grahams and the like. Good luck!