Private equity-backed Archipelago Learning Inc's shares rose in their first trading session following the company's initial public offering, which priced in line with expectations on Thursday.

Shares of the provider of subscription-based online education for students between kindergarten and grade 12 opened on Nasdaq at $19, or 15 percent above the IPO price. Later on Friday morning, they were at $18.50, up 12.1 percent.

The Dallas-based company sold 6.25 million shares for $16.50 apiece, within the expected $15 and $17 range, and raised about $103.1 million in its IPO on Thursday after the markets closed.

Half of the shares in the IPO were offered by the company itself, and the other half by owners such as Providence Equity Partners. That private equity firm will still own 48.9 percent of Archipelago's shares after the IPO is completed.

In the nine months ended Sept. 30, Archipelago had revenue of $32.7 million, an increase of 46.4 percent over the year-earlier period, and profit of $6.9 million.

The IPO was lead-managed by Bank of America Merrill Lynch and William Blair & Co. The underwriters will have the option to purchase an additional 937,500 shares.

(Reporting by Phil Wahba; Editing by Lisa Von Ahn)