If it is felt strongly by your current group of members that the President (or even the entire board) should have some sort of experience at a lower level, why not push for an update to the bylaws before the elections? With the current circumstances it might be best if the motion not come directly from you, but I would imagine that many of your members who have been busting their behinds for several years are probably taking offense at a new person with no experience coming in and telling everyone about all of the change that is needed (essentially stating that the current group has done a poor job). If your current bylaws allow it you may even be able to make a motion to postpone elections pending a vote on proposed bylaws changes.
If it helps any at all I have seen a lot of bylaws that include stipulations regarding who may run for a board position. Our group requires that candidates have attended at least one general meeting in the past 6 months, have chaired at least one committee, and have been a dues paying member at least one month prior to the nominations being announced (which happens 1 month before elections).
In addition to rules governing who can run for a position, we recently made a change regarding who can vote in an election. After discovering that a situation similar to what you describe regarding friends of a candidate who had never participated in any of our group's activities coming to the meeting for elections, paying their dues, voting, and then disappearing from the group again, we decided that change was in order. So we passed an amendment stating that to vote in an election a person must have become a dues paying member by the monthly meeting preceding the elections, and must have attended at least one general meeting in the current school year. Since nominations are not announced until the meeting preceding elections this cuts down on the possibility of the same thing happening again.
And as yet another safeguard you could also consider instituting a nominating committee. I'm not certain how these run in other groups, but in ours it is made up of a minimum of 3 people (5 or more and always having an odd number is better). They start meeting in December (our elections are in March). They are responsible for contacting all members and all staff at the school (members or not) to ask if they know of anyone who may make a good board member who they would like to nominate. Nominations can also be submitted anonymously by filling out a form and placing it in the nominating committee box at the school. Once the nominations have all been received, the committee then reviews each name individually without regard to any of the others and determines whether this person meets the requirements set forth in the bylaws, what their qualifications are, and any awareness of specific issues that may be of concern. The discussions of the committee are held in the strictest of confidence. No minutes are required to be submitted, and any notes taken should be destroyed after the elections have taken place in order to encourage frank and open discussion. The nominating committee then decides by vote (secret ballot required) whether or not the person in question should be placed on the ballot and in what position. After this process is completed they are responsible for contacting all nominees and asking if they are willing to accept a nomination, and informing them if they have have missed any of the requirements such as paying their dues or attending a recent meeting so that they can rectify this matter in a timely manner. If anyone is unwilling to accept their nomination the committee strikes them from the ballot and presents the nominees at the monthly meeting preceding elections. On election night nominations can be made from the floor before voting takes place, but these nominees must still meet the requirements in the bylaws regarding chairing a committee, paying dues, and meeting attendance. While the whole process may sound a bit harsh in terms of a group of people making these types of judgment calls, the committee is open to all volunteers who have paid dues prior to the first committee meeting, and helps to eliminate candidates who want to run for reasons that are not necessarily in the best interest of the group (like carrying out personal vendettas, getting elected to the school board, or bringing the group more in line with the desires of another group like the teacher's union issue you describe). It is also worth noting that the current president is not allowed to serve on the committee at all, current board members are encouraged not to but not outright forbidden, and if a member of the committee is nominated they are required to leave the meeting during the time that they are being discussed and are not allowed to vote regarding their own candidacy.
I don't know if any of this actually helps you, and I should probably apologize for my lack of brevity (which is a going theme of mine on the boards in all honesty). For me personally I prefer more details in the posts I read than not enough, so I tried to include it all. In any case I hope you can gain some sort of assistance from at least some of it.
