Educational companies sell an endless supply of alphabet learning games. There are online programs, letter software, and a myriad of workbooks aimed at teaching preschoolers letter recognition. I've found the best games to be ones we make at home using markers and paper. One we made today was to help with recognizing upper and lower case letters. We call it "The Letter Match Game."
You can tailor this to meet your own needs, using colored papers, holiday-specific designs, substituting words for letters, etc... Here's how we make and play "The Letter Match Game."
Fold the papers so you have twelve rectangles divided down the middle with a crease. Cut along the middle crease and then cut out the rectangles. Gather a stack of rectangles and fold them in half so you have two squares. Cut in half. Write all the uppercase letters and then the lowercase letters on their own squares. Lay them out and review all the letters. Ask your child to pick if they want to be uppercase or lowercase.
Help them spread the letters out faceup on their side, in no particular order. If you're just starting letter recognition, then it might work best to put the squares in ABC order. Spread your letters out faceup on your side. Have a little scoring paper to keep points.
The child goes first and asks if you have a match for a certain letter. They can choose any letter on their side that they want a match for. They must say the letter, not just hold up the paper. You then look for the matching letter and hand it to your child. If you can find the match within 20 seconds, (you can increase or decrease this time depending on ability) you get a point. It's now your turn to ask for a match. Your child then looks for the matching letter and hands it to you. If they find the matching letter in 20 seconds, they get a point.
If you or your child doesn't find the match in the alloted time, the person asking for the match gets a point and another turn. The letter just goes back into the mix to be used on another turn.
To make sure Avlyn comes out a point ahead, I will pretend not to be able to find a match in the 20 seconds a couple times. This keeps her from getting frustrated, because there are times when she does not find the match in 20 seconds and loses her point and her turn.