Here at Zacks, we focus on our proven ranking system, which places an emphasis on earnings estimates and estimate revisions, to find winning stocks. But we also understand that investors develop their own strategies, so we are constantly looking at the latest trends in value, growth, and momentum to find strong companies for our readers.Looking at the history of these trends, perhaps none is more beloved than value investing. This strategy simply looks to identify companies that are being undervalued by the broader market. Value investors use tried-and-true metrics and fundamental analysis to find companies that they believe are undervalued at their current share price levels.Luckily, Zacks has developed its own Style Scores system in an effort to find stocks with specific traits. Value investors will be interested in the system's "Value" category. Stocks with both "A" grades in the Value category and high Zacks Ranks are among the strongest value stocks on the market right now.One stock to keep an eye on is Sterling Construction (STRL). STRL is currently sporting a Zacks Rank of #1 (Strong Buy), as well as a Value grade of A. The stock is trading with P/E ratio of 10.69 right now. For comparison, its industry sports an average P/E of 15.21. Over the past year, STRL's Forward P/E has been as high as 12.85 and as low as 7.54, with a median of 10.84.Value investors also frequently use the P/S ratio. This metric is found by dividing a stock's price with the company's revenue. This is a popular metric because sales are harder to manipulate on an income statement, so they are often considered a better performance indicator. STRL has a P/S ratio of 0.45. This compares to its industry's average P/S of 0.68.Finally, investors will want to recognize that STRL has a P/CF ratio of 7.57. This metric takes into account a company's operating cash flow and can be used to find stocks that are undervalued based on their solid cash outlook. STRL's P/CF compares to its industry's average P/CF of 10.52. Over the past year, STRL's P/CF has been as high as 8.94 and as low as 4.06, with a median of 7.38.These figures are just a handful of the metrics value investors tend to look at, but they help show that Sterling Construction is likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, STRL feels like a great value stock at the moment. 5 Stocks Set to Double Each was handpicked by a Zacks expert as the #1 favorite stock to gain +100% or more in 2021. Previous recommendations have soared +143.0%, +175.9%, +498.3% and +673.0%. Most of the stocks in this report are flying under Wall Street radar, which provides a great opportunity to get in on the ground floor.Today, See These 5 Potential Home Runs >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Sterling Construction Company Inc (STRL): Free Stock Analysis Report To read this article on Zacks.com click here.