Sorting Colors with Cardboard Tubes--this website has lots of great ideas for preschool fun! Could be fun with cardboard tubes and acorns and numbered baskets for a fall sorting activity.
If you're teaching your toddler the alphabet, you'll want to check out this huge list of playful alphabet activities for 2 year olds! While learning the alphabet, kids had opportunity to learn new words.
Simple Shape Activities for Preschoolers - Teaching 2 and 3 Year Olds