Whether or not it is too early depends largely on your educational philosophy. You mention your "students" so presumably you are teaching as part of a school. In this case, the parents enrolled their children based on an idea of the school's philosophy. That philosophy should guide your teaching.
By age three, most children can recognize some letters. So, developmentally, they are prepared to recognize the letters of the alphabet.
However, there are philosophies that believe in delaying formal instruction until later, focusing instead on play, manual dexterity, or outdoor exploration at this age.
Most schools take a middle ground. Most of the time is spent exploring opportunities for open-ended play and art, as well as storytelling. Puzzles and other toys with letters are available for children who are drawn to these. The teacher may have a letter of the day and practice phonics with the students, pointing out familiar animals and objects that begin with these letters.
Some schools introduce formal academics very early and use worksheets and drills in order to prepare for the increasingly academic kindergarten programs. Research has shown little long-term gain from this form of education but there is definitely a market demand for it and so there are schools that offer this method of instruction.
Yes, I recommend teaching the alphabet order and letter recognition to your 3 year old. It's not too early to begin, although it may take time for your child to master the skills-that will depend on the child as each develops at different paces.
Keep learning fun, but teach as much as possible. I've included links that will help teach and your child will enjoy. Scroll through the activities and worksheets available from education.com to find helpful ideas and Starfall.com is a online program that your 3 year old should be able to work with freely at her own pace and it is used in schools by the Kindergarten classes.
Good question. I was always taught that age 4 was the time to "introduce" the alphabet, but the preschool that I am currently working at begins with the letters at age 3. I have been teaching preschoolers for 16 years, and I feel personally, that it is too much too soon. However, the elementary schools are expecting so much of children entering Kindergarten, that preschools are pressured to make children ready, and that means sometimes doing things that would have been considered not age appropriate years ago.
My co-teacher and I are trying to introduce the letters in a fun way with
songs and activities such as stomp around the "S", bounce on the "B", putting feathers on the "F", and finding the letter in the room. Bear in mind that you will have the opportunity to expand on the letters the following year. Each child is different and learns at a different pace. Some will pick up on the letters right away at age 3, while some will be more confident with the letters at age 4 and even 5. I guess what I'm saying is that you can try, but don't be surprised if the 3's don't recognise very many of the letters when you evaluate them.
Identifying the letters and writing them are two very different things at this age. From a writing standpoint, 3 year olds need to scribble alot and imitate lines and circles. These as you know are foundational lines and circular movements needed for later letter writing. Please don't be pressured into moving our little ones too quickly into academics when they have so many motor skills, perceptual skills, and language abilities to learn (not to mention social) at this age.
At my daughter's preschool, they had 26 paver stones each with a different letter of the alphabet. They put these stones in order with space between them and in a fun circular path. My daughter and all of the kids loved to walk on the stones and recite the alphabet. When my daughter had mastered that task, she had fun randomly stepping on a stone and trying to identify it or jumping over a stone and trying to identify the letter on the stone she jumped on. When she had mastered the alphabet going forwards, she had fun doing the alphabet backwards by starting with Z and identifying the letters as she walked on each stone. It was a lot of fun for her and the other children. Since these paver stones were in the garden right at the entrance/exit, I knew I had to accommodate a few extra minutes for her to do these alphabet activities before leaving the premises to go home for the day when I picked her up from preschool.