Lindbergh Schools has retained its Aa1 bond rating, according to Moody’s Investors Service.

Moody’s is a national credit rating agency that provides an independent opinion regarding the school district’s financial stability. The Aa1 bond rating is the highest a school district can earn.

Moody’s announced its decision Friday, days after the Board of Education voted unanimously to adopt a resolution seeking competitive bids for the sale of roughly $34 million in general-obligation bonds.

Bids will be accepted until 10 a.m. Sept. 9, and the Board of Education is scheduled to consider approval of the bond sale when it meets that night.

Lindbergh voters authorized the issuance of $34,035,000 worth of bonds when they approved Proposition G — for Growth — in April.

The bond issue will increase the district’s debt-service tax rate by 21 cents, to 68.3 cents per $100 of assessed valuation from 47.3 cents.

A total of $23.9 million of the bond proceeds will fund the construction of a 650-student elementary school on the nearly 10-acre Dressel School site at 10255 Musick Road.

As proposed, the new elementary school will open in August 2017.

In the meantime, the district continues to face aggressive enrollment growth.

Besides the construction of a new elementary school, $3 million of the bond issue proceeds will fund some critical needs at Lindbergh High School, including doubling the size of the cafeteria, creating two science classrooms from existing classrooms, converting a record-storage room into two new classrooms, modernizing the library and replacing the wood floor and bleachers in Gymnasium 3.

The building projects will have $3 million in contingency.

In addition, proceeds from the bond issue will be used to retire roughly $3.5 million of debt incurred when the district purchased the Dressel site for $1.94 million in July 2011 and property adjacent to Long Elementary School in December 2012.

To fund the purchases, the Board of Education approved the issuance of certificates of participation, or COPs, totaling nearly $3.5 million. The COPs will be retired, with the remaining debt rolled into the bond issue and paid by the debt-service fund.

The school district now spends roughly $300,000 per year in operational revenue for that debt.

In a separate matter Aug. 11, the board voted to award a contract to Tri-Co. Inc. to construct a play field at Sappington Elementary School at a cost not to exceed $269,300.

Tri-Co submitted the lowest of six bids for the field, which is being built on 1.9 acres the district consolidated into a single lot by purchasing four adjacent homes.