Hiya, hope this isn't too late, I'm not sure what items would constitute short interest, interactive duration is possibly linked more to individual preference or curiosity, & no worries about the children being in freeplay rather than captive/under guided instruction. If you've ever setup a stall or attended a bootsale/fayre slightly later than planned you'll know interest & captivity is potentially there
Would growing for the season be suitable? A basket -
seagrass is nice, with seeds: cress, sunflower, nasturtium, sweet peas, peas, runner beans, plastic pots, twine, label sticks, scoops and a bowl of soil, gardening gloves - mixed sizes, pink wool for worms maybe, posters & books would all be good but may need an adult nearby for risk.
Open questions, have you grown xx .. where was that .. which flower picture do you like .. what job do worms do/ how do worms help the plants grow, what do seeds like to grow/how do seeds grow - soil, water, warmth, light, air,
germination, roots, stem & leaves ..
Alternatively you could look generally at a room, this would be more along the lines of a traditional treasure basket - looking for a range of materials made from metal, wood & paper, plastic, fabric, natural items, textured, colours, items that have warmth or are cooler: eg: Kitchen: Pots, pans, spoons, plastic scourers, tea towel, cups, keys, bowls .. you may find the children are less interested in these at 3-4yrs as they'll possibly be more familiar with them / moved on from a basic need to explore by mouth & hand passing - in expanding their use you might find they ask to build on your providing them by taking them off into role or other play areas.
Other display/basket ideas could be 'our contruction toys, to build, Jungle, Safari, Island - boats, treasure maps and spades
Hope this helps
xx
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