Some of my students need more than just a song or me teaching them what the silent e's job is. I have found a lot of times they need a visual to go with it. So we have gotten into the habit of drawing the arrow over the consonant to point to the vowel that says its name. This seems to work for my students that couldn't remember long vowel sounds on their own.
Here is how we have are handling vowel pairs. We of course know the song- two vowels go walking, the first one does the talking. But the song in itself didn't make sense to my students. So we had to act it out by having two vowels in a word, the person holding the first vowel holds the board out farther than the others, the person holding the other vowel holds their hand over their mouth to show that vowel doesn't talk. This has worked wonders for my group that just couldn't switch over from a short vowel to a long vowel. All I have to say is vowel pair and they remind me, "oh, I remember that is like when she held the e and he held the a with his hand over his mouth!". Some of my students have to work through this little scenario to be able to remember how to handle the two vowels. But hey, whatever works!!