Unlock the following items by talking to Tortimer on the corresponding days:
ITEM - DAY Cool Globe - Talk to him on Nature Day. Leaf - Talk to him on April Fool's Day. Picnic Basket - Talk to him on Labor Day. Resetti Model - Talk to him on Groundhog Day. Sailboat Model - Talk to him on Explorer's Day. Wheat Bundle - Talk to him on Harvest Moon.
