Any type of matching game will help children build their memories, and these games are portable enough to be played anywhere. Make your own matching games by cutting index cards in half and drawing letters or numbers on them. Draw each number or letter of the alphabet on two cards and spread all the cards out, writing-side down. Children must turn two cards over. It they match the child gets to keep the pair, but if they don't the child must turn the cards back over and let the next child take a turn. Ask children to identify each letter or number card they turn over.
Scavenger hunts can be played in a single room, throughout an entire house or school or even outdoors. Rather than telling children what specific items they must find, give them a list of types of objects to find. For instance, ask children to find objects that are rectangular or orange, or ask them to find images of the letter M. Many 4-year-olds can't yet read a list of objects, so ask them to find one thing at a time.
Use bingo to teach children about shapes, numbers, colors or letters. Make your own boards by drawing grids of 25 spaces onto paper. Decorate each space with a shape or number, then make a set of cards with matching images. Each board should have the pictures in a different order. Give each player 25 small paper squares, then start pulling out cards one at a time. Children must cover the corresponding spots on their own boards with paper squares. The first player to fill an entire row wins.
Help children learn to spot the letters in their names using a pot of pretend alphabet soup. Print the alphabet onto paper, then cut the letters apart. If you're playing with a large group of children, you'll need a few dozen of each letter. Put all the letters in a pot and give each child a chance to stir it up. Let each child pull one letter out of the pot at a time. If it's a letter in her name, she keeps it. If not, she puts it back. Keep going until children have spelled their first and last names.