You can accomplish several different objectives on these alphabet pages. Do whatever your child seems ready for at the time. 

1. Learn to recognize and name the letter.

2. Learn the sound the letter makes.

3. Learn the shape of the letter and how to draw it.

4. Learn the sight word.

5. Learn a few kernels of information about the sight word.

1. Dig deep grooves in that little brain by involving multiple senses in the learning process!
Trace the giant letter at the top of the screen with your child's finger while saying the letter's name, then the sentence, placing special emphasis on the sound the letter makes in the word. For example, "We hear the sound of A in AAAAAAAAAAAFRICA!" Repeat throughout the day, being as silly as possible! Write the letter with your finger in peanut butter on toast, or in marshmallow topping, or in sand, or dirt, or freshly vacuumed carpet, or on bubbles in the tub, or in the snow, or wherever you like! Of course crayons and paper work too! Make a stencil for your child so he/she can create a letter successfully. Hang everything your child produces in a prominent place where he/she can visually reference it and remember the sounds and shapes he/she learned. 

Try exposing the child to the sight word in different environments. Sponge letters in the tub, magnets on the fridge, on a chalk board, on a white board, in the newspaper, in a book, etc. Pronounce it in the same way each time, with great enthusiasm and if possible silliness. Tickling is a great reminder that learning is fun. Remember to repeat the words you've learned in the past, and also to teach the child as many words as he/she seems interested in. Favorite song is "Twinkle twinkle"? Learn the word STAR. Like Sesame Street? Learn the word ELMO. Every word he/she learns makes it easier for him/her to learn the next one. There is no limit to a child's brain! Pack it in!