A couple months before we had purchased the Your Baby Can Read kit, but had only shown it to him a hand full of times. The flash cards that were dropped when we learned he was reading had come from Your Baby Can Ready, but he had not seen them enough either to learn to sight read from them.
Once we learned he was reading, we started using the a magnetic doodle board to write words. We have two older boys who are active in sports, so the little guy spent quite a bit of time waiting on them for games or practices and using the doodle board was a fun way to pass the time.
I had a strong suspicion that he was learning to read from watching Signing Time, but was not sure how to prove it. However, there were a few words that did not over lap. So one day while using the doodle board I wrote "eat" (only in Singing Time). Sure enough he signed eat. So then I knew that Signing Time was the real program teaching him to read. It totally made since, because the word is always shown while the sign is being demonstrated. After this time I started playing his daily video with the subtitles on, figuring it could not hurt to give him exposure to even more words.
While I knew he was learning to sight read from watching his daily video, I still felt the need to test this theory. When we got our next new Singing Time DVD (Volume 13, Welcome to school) I let him watch it a couple weeks before I wrote one of the words on the doodle board. I wrote "pay attention" and without any hesitation he signed pay attention and made a verbal word attempt. Not only was Signing Time teaching him to sight read, it was also encouraging him to make attempts at saying some pretty big words. Again I was amazed.
While I was praising my son for his awesome accomplishment, he looked at me and said "I sma" while he signed smart. Another word he picked up from his new video. Yes little man. You are smart.