Public Class Form1

    Private Sub Button_Click(sender As Object, e As EventArgs) Handles Button.Click
        Timer1.Enabled = True
        If Timer1.Enabled = True Then
            Label3.Text = Val(Label3.Text) + 1
        End If
    End Sub

    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
        Label2.Text = Val(Label2.Text) - 0.1
        If Label2.Text = "0" Then
            Timer1.Enabled = False
            Label2.Text = "15.0"
            MsgBox("Time's Up. You Scored " & Label3.Text & ".")
            Label3.Text = "0"
        End If
    End Sub
End Class