Charles Schwab’s latest low-cost exchange-traded funds were launched Friday, boosting the firm’s existing lineup to six ETFs. They are:

• Schwab U.S. Large-Cap Growth ETF (NYSEArca: SCHG)
• Schwab U.S. Large-Cap Value ETF (NYSEArca: SCHV)

Schwab’s new offerings, which will track Dow Jones indexes, come with low operating expense ratios of 15 basis points—among the lowest in the industry—and commission-free online trading in Schwab accounts.

SCHG and SCHV join the other four Schwab ETFs, which were launched on Nov. 3: The Schwab U.S. Broad Market (NYSEArca: SCHB), Schwab U.S. Large-Cap (NYSEArca: SCHX), Schwab U.S. Small-Cap (NYSEArca: SCHA) and Schwab International Equity (NYSEArca: SCHF).

So far, Schwab’s recipe seems to be working for them. In little more than a month since inception, the firm’s four ETFs have garnered more than $100 million in assets and are trading with generally high liquidity and low spreads.

Schwab isn't done. The company said that it plans to launch two additional ETFs covering emerging markets and international small-cap equity in January 2010. The funds are Schwab International Small Cap Equity (NYSEArca: SCHC) and the Schwab Emerging Markets Equity ETF (NYSEArca: SCHE). These funds should come with a price tag of 35 basis points.

You can read previous coverage on Schwab's family of ETFs here.