private void lecturesToolStripMenuItem_Click(object sender, EventArgs e)
{
Lectures fr2 = new Lectures(this);
fr2.MdiParent = this;
fr2.Show();
}
private void button1_Click(object sender, EventArgs e)
{
Lectures fr2 = new Lectures(this);
fr2.MdiParent = this;
fr2.Show();
}