function resetClasses() {        
    document.getElementById("strosbergA").className ="teacherlink";  
    document.getElementById("snyderA").className ="teacherlink";
    document.getElementById("bakerA").className ="teacherlink";
    document.getElementById("kozikA").className ="teacherlink";
}

function strosberg() {
    resetClasses();
    document.getElementById("strosbergA").className ="teacherlink2";
}

function snyder() {            
     resetClasses();
     document.getElementById("snyderA").className ="teacherlink2";
}

function baker() {            
     resetClasses();
     document.getElementById("bakerA").className ="teacherlink2";
}

function kozik() {            
     resetClasses();
     document.getElementById("kozikA").className ="teacherlink2";
}