I knew that my little clients would love this ....they were so tuned into valentines and hearts. I cut the large white circular piece (from a large container that held protein powder) to function like a belt. In fact the two ends buckle together and it can be placed on the head, around the waist, on arms or used on the ring stack pole. Cut up different sized containers to get different sized "belts" to weave onto. There seems to be a thin line between stringing and weaving but i will call this "weaving" because I was teaching them to insert the end through the 2 notches in the hearts and then push them down. This is easy to simplify by asking them to only insert through 1 notch or complete the 2nd notch after the first one is already inserted for them. Removing them also took some nice motor planning and hand strength.
These and many other activities are described in the Kindle book The Almost Complete Plastic Bottle Activity Book
Consider making the following manipulation activity that involves inserting and/or removing the arrow from a heart....Source: Make-your-own Valentine Hearts and Arrows by RecyclingOT on Rumble