Outdoor writing - use some of those old cigar boxes? Also, need to develop the idea of provocations outlined in this link - and be ready to note the conversations and actions they generate in the children!
This word building activity travel kit is perfect for toddlers and preschoolers for road trips and long car rides and you can customize it with sight words, color words, word families, or whatever your child is currently learning. Great for a summer learning activity.
Word Building Activity Travel Kit | I Heart Crafty Things