Over the past few years, I’ve had dozens of parents recommend early reading books and programs. The books we’ve had the most success with and have been recommended most often are the Bob Books. They’re inexpensive sets of reading basics books that give kids a sense of accomplishment and pride by helping kids quickly learn to read the whole book. My son developed sight word recognition very quickly with these (identifying “the” and “and” for example) and did very well with the repetition and phonics basics.
The stories are boring and weird, and the illustrations aren’t exactly richly detailed, but these books get the job done. And they get the job done quickly. I’d definitely recommend these to parents of kids moving into kindergarten, especially if you need a head start over the summer or you’re not sure where to begin. I think they also make great gifts for kids turning four!
My son was so excited about his Bob Books accomplishment that he actually brought one in for special show and tell at school and “read a whole book” to his class.

It’s amazing how skilled children can be if we just expect greatness out of them.
The three year old I work with is writing full sentences now. Insane!