Blocks, puzzles and other hands-on toys that have long been mainstays of children's play are still best at teaching some skills needed for success, according to a research review.

Although so-called screen-based entertainment—including computers, video games and cell phones—can keep young children occupied, technology is less effective than more traditional toys in teaching spatial reasoning to preschoolers, the US researchers say.

"Skills, including early geometry and knowing the names of shapes, help kids learn the math skills they pick up in kindergarten. And if they already have those (before they begin school), they are ahead of the curve," says lead author Brian Verdine.