I work in a preschool classroom and we do a letter of the week. The children in my classroom are three and they have been doing great with this method. During circle time on monday I will introduce our new letter of the week. I have big foam letters and I will show them the one pertaining to the week. I will say what the letter is and then have them repeat it. We will then spend a little time on it each day. The second day, we discuss the sound of the letter and words that begin with that letter. The third day we will trace the foam letter with our fingers, I will come up with a simple way for them to remember how to write it. For example; for the letter "A" I had the children say up, down, across. For the letter "B" we said up, around, around. The children will say the words as they are tracing the letter. The fourth day we will write it with a marker/pencil on a big piece of paper. Then on the last day, we review what we had learned. I feel that repetion is a great way to teach something to children and have them remember it. Naturally when teaching a new skill to a child you must look at their age and development level. I hope this answer was useful.