A marketing campaign promoting Rhode Island’s strengths, a ‘‘buy local’’ initiative, and nine other projects will share $630,000 in grant money from the Rhode Island Foundation as part of its pledge to help jump-start the state’s struggling economy. The foundation announced the grant awards Thursday as part of its 1 million pledge to projects stemming from last year’s ‘‘Make It Happen RI’’ forum. Foundation chief executive Neil Steinberg said the projects turn rhetoric into action. Rhode Island has one of the worst unemployment rates in the nation, at 9.8 percent in January. The projects are aimed at creating jobs, preparing people for higher-paying employment, and connecting unemployed workers with job openings.