Start by drawing a large letter m on the board for scholars to see. Do they know what letter this is? Once you've demonstrated the sound it makes, use these tips to help them make the same sound. There is even an audio pronunciation guide here if you want to use it. Brainstorm some words that begin with m, then print several letters, a few of them m, on the board. Play a game as your point to letters; if you point to an m, scholars say its sound. If it's another letter, they stay silent. There are some good letter card printables here, too.