Because these kids are not in all day school yet, home is still their main source of language and learning. Preschool children no longer qualify for Early Intervention which means they (might) get some preschool services through their school district BUT families miss out on the parent training that comes with Early Intervention.
If you have questions about how you can help your preschooler at home I have some resources that might help!
Preschool Development - This is the page I just finished with information about preschool language skills and tips to help you work on some of them
Helping My Preschooler Learn to Learn - This is a blog post featuring some ideas on ways to help a preschooler learn new things
Summer Pre-K Program - In this blog post I share a program that I use to introduce or review new letters/sounds the summer before kindergarten.
Have fun with your preschooler and should you have questions or concerns don't be afraid to reach out to your pediatrician, preschool teacher, or SLP!