Public Class Form1

Private Sub Child1ToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Child1ToolStripMenuItem.Click

Dim ch1 As New Child1

            ch1.MdiParent = Me

            ch1.Show()

End Sub

Private Sub Child2ToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Child2ToolStripMenuItem.Click

Dim ch2 As New Child2

            ch2.MdiParent = Me

            ch2.Show()

End Sub

Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click

Me.Close()

End Sub

End Class