We are homeschoolers, and our wacky early education program goes like this:
We play UNO to help identify colors and numbers. Some of the younger set can't hold their cards very well, but they are allowed to spread the cards out in front of them on the table so that older kids and adults can help. The speed at which they learn the colors and numbers is miraculous with this game.
We practice writing names just by plain, ordinary copywork. Get some imaginary line paper, copy his name in your neatest print, and help him practice copying his name every day.
The best way that we have found besides flash cards for letters and sounds is through videos and TV programs such as Sesame Street or the one that you mentioned above. You can probably find some really great videos for beginning readers at your local or school library. Look through his toys and see if you have any games or toys that help with the ABC's. My kids had an electronic toy that had push button letters that would say the letter, sound, and an example word out loud when the button was pushed. Other than that, you can just hold up the flashcard, have him trace the letter with his finger, and practice the letter sounds out loud together. I also teach Girl Scouts, and I have noticed that the youngest children practice extensively on letter sounds. They spell by saying each letter sound out loud. It's really funny to watch them trying to write in this way, but it works. I'm sure that you could teach this method to your four year old. For example, if the child is spelling the word "cat", the child would start saying "cat.....ku, ku, c....aah, aah, a....tu, tu, t..." Even if you don't have him trying to write these words down, you could still show the words and practice breaking down the sounds in this way. At the dollar stores, you can usally find alphabet coloring books. We had some that featured a new letter on each page, and each page was filled with objects to color that began with that letter. This can be fun! Enjoy your future kindergartener.
Have a Great Day!
L. Santiago