We give our kids lots of time to play, play, play with these items. We sit with them and play, too. Sometimes we help to develop a concept, but other times we just work with them for the sake of playing.
Counters are great for lots of things:
making sets of less, more, and equal to,
A large collection of anything could be counters: beans, poker chips, buttons, pictures, beads, animal crackers, fish snacks, raisons, cereal…