ANSWER: Your PTA membership needs to vote if they would like to endorse a levy/bond campaign. If the PTA endorses the campaign, then you can make public a statement about that endorsement. If there is not a vote for an endorsement then the PTA can only share facts.
A PTA may donate to a levy/bond campaign if the membership has approved such an expenditure through their budget. However, they need to be careful of IRS guidelines if you are a 501(c)(3) corporation which states that you can only contribute an insubstantial part of your budget including volunteer hours. The IRS does not define what insubstantial means but it is about 3-5%. Or, your PTA can file a schedule H with your 990.
We have resources to assist local units in staying within the legal boundaries for 501(c)3 organizations (this makes sure you comply with the rules for campaigns and elections for non-profits so you can keep your non-profit status). On the WSPTA website, under ADVOCACY and LEGISLATIVE BASICS is a document on taking positions in campaigns and elections. Follow this link for the document: http://www.wastatepta.org/advocacy/leg_basics/PTAsTakingPositions.pdf
Additionally, when PTA parents get more involved and learn how the local school district levy and bond campaigns and elections work, they may take positions as volunteers on the local levy citizens campaign committee.