My son's - He chose the medium and we thought of things together that he liked or fit the season to make it creative.
50 "stars" + 3 strings for each of 13 "stripes" (that's 39) + 11 strings to spell out "100 strings" =100 strings
(the "i" got 2 - one for the stick, 1 for the dot)
Foam "beads" strung on red pipe cleaners and shaped/twisted into a heart shape.
(he liked flags a lot when he was 5-6 years old. The other was to use up some foam shapes we needed to purge from the craft pile)
Ms. Independent insisted on doing her own thing and refused to accept any of my creative suggestions. She finally agreed 10 stickers to a page so that it would be easy to count (and good practice counting by 10s)
The next year (drat! no picture was taken) - She wanted to use beads, so we strung them on craft wire. She wanted it flower shaped, so we attempted to bend/curve & twist the wire into a flower shape with each petal having 10 beads...it mostly cooperated, and it turned out cute - I take pictures of EVERYTHING - where is my picture of this?
This year we had TWO projects as my twins are in kindergarten -
My very independent twin decided she wanted a chain "like we make to count down for the end of school".
I suggested felt (since I had most of what we would need) and it wouldn't get torn on the way to school.
(Other than directing and making sure she knew how to use the staple and overseeing she stuck with 'the plan', she did this pretty independently.)
The other looked through my craft surplus and decided to use these little fuzzies (dollar tree - they only come 80 to a pack, so I did have to buy more)
Fuzzies strung on string with a large-eye needle - like you would popcorn for a Christmas tree.
We did find that it was difficult to keep them centered on the needle so that they wouldn't come right off the string - some got a second stitch through it once it was pulled to in place.
I did have to supervise this one a little more:
First of all, there's a needle involved. Secondly, she would push them down the string so hard they all squished together so you couldn't tell one fuzzy from the next. Also, she's the twin that always "needs" help.
Both of these are in sets of 5 (another good counting skill)