Hi M.,
As a certified teacher and certified parenting teacher/speaker, I think it is important to know that toddlers need the adult to take the lead in reading toddler stories, reciting and teaching simple rhymes, singing simple songs, stacking blocks/cups, scribbling w/ crayons, playing on playground equipment (gross motor skills), pretend grocery store, visiting the library, "paint" the driveway with water, "sort" laundry (make piles of socks, etc.., play "zoo" with stuffed animals, visit a zoo, take him grocery shopping and talk about the foods are placing in the cart, let himparallel play with other children his age, go to the beach (digging, swimming, picnic)...ETC...So I can't say that a method is best!
As far as flashcards go, you can accomplish the same thing w/ simple toddler board books that are made up of photos. If your child enjoys the flashcards...they are fine to use! Yet, if your son does not show an interest in them...then, stop.
Toddlers usually love short rhyming stories. As a toddler gains language skills...s/he will recite some of the words!
Toddlers usually love music...Put on some music and dance !
Purchase a CD that has the following songs: ABC's, Hokey pokey,
Twinkle, twinkle little star, etc...Sing them in the house...Then, play the CD in the car and sing them.
When my kids were little, I set up a water table in the back yard. They would stand at the water table and fill small tupperware containers, dump the water, fill it again, stir the water with a plastic spoon, make "soup", etc... This is a science lesson !
Toddlers can be very self-centered...which is normal. So "teaching" sharing (over time) is important. Also, tantrums usually come into play. So, teaching a toddler that while it's ok to tantrum...redirection given by the parent teaches self-control and social/emotional growth, too.
Some toddlers love to be at the playground for hours, others like to play with indoor toys...some with sit and listen to 5 books in a row, while another toddler with sit for 1 story.
When my daughter was 3, she loved dogs ! So, I copied 15 separate pics of dogs...all different breeds (a black poodle, a white bichon, etc..) I would tape a pic of 1 dog behind the drivers seat and in front of my child.
She would pick a "dog of the day" to tape to the seat. We would talk about the dog...and extend on the language. **When she was 3, her favorite learning game was to play "mailperson." She would "write" letters, put them in a bag and "deliver" them to the stuffed animals that were spread out ALL acroos my LR floor. Her other favorite thing to do was to clean...sweep, dry swiffer the floor, etc...