These button sorting cups make a great toddler activity to work on matching and fine motor skills.
Match shapes to outlines on cardboard. You can extend this by sorting the shapes or talking about the different attributes of shapes. You can even use the felt shapes to combine and make new shapes and objects once your child is older.
The Elementary Math Maniac: Quick and Fun Math Practice for Little Kids. Another cute way to show number recolonization and one to one correspondence.
Common Core Connection
Math Visual Aide. Bottomless cups - students drop manipulatives through!
Teaching Addition with Popsicle Sticks - you could use any two different colored stuff around the house: straws, strips of colored paper, two different kinds of dried pasta/beans, etc.
Putting right amt of beads onto pipe cleaners. Next time, don't use fuzzy pipe cleaners. Use masking tape so numbers don't fall off. Needed supervision.