Aside from some pre-measuring and cooking activities, I haven't done too many math activities with my son. With the possibility that he will begin Kindergarten next year (he'll be eligible but barley 5, so I may hold onto him one more year) I figured it was time we start. Of course, as an advocate for play, I wanted it to be somewhat open ended, but I wanted a bit of structure as well.
Peeling foam stickers is excellent fine motor practice!
Once he placed his stickers, we counted how many he placed in each column. I reminded him what a "1" looked like and let him write the number on his own.
For some more Halloween math ideas check out:
Little Lucky: Halloween Activities (this site is in Romanian but she has Google Translate)
3 Jewels in my Crown: Pumpkin Seed Math