Shares were up 94 cents at $4.65 - the highest percentage rise on the New York Stock Exchange on Thursday morning.
Fourth-quarter profit was $29.4m, compared with a loss of $44.1m a year earlier.
Net sales jumped 37 per cent to $188.6m, ahead of its forecast of $155m to $170m.
Analysts were looking for earnings of 24 cents a share on revenue of $167.9m.
The company expects net sales to rise 10 to 20 per cent in 2010. The average growth estimate was 12 per cent, according to analysts.
For the first quarter, it forecasts that net sales will be "significantly above" the full-year growth rate of 2010. It also expects its customer base to more than double to between 6,000,000 and 7,000,000 after Christmas 2010.
CEO Jeff Katz said the firm saw strong Christmas sales for Tag and Tag Junior and its new line of My Pal Scout toys (pictured).
"We are entering 2010 with momentum and lean retail inventories ... We expect significant sales and earnings growth to continue in 2010 and beyond," he said.
The company also plans to expand its distribution to include book retailers, grocery stores and other outlets.
Meanwhile, in a management reshuffle, Katz will take over the role of executive chairman from 1st March, while Finance Chief Bill Chiasson will succeed him as CEO.
The firm also named Mark Etnyre, who joined LeapFrog two years ago from Microsoft, as CFO.