Вы можете использовать встроенный BooleanToVisibilityConverter . Вот рабочий образец:
<Window x:Class="WpfApplication16.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:my="clr-namespace:WpfApplication16"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="b2v" />
</Window.Resources>
<StackPanel>
<CheckBox x:Name="chk" Content="Show There" />
<TabControl>
<TabItem Header="Hello" />
<TabItem Header="There" Visibility="{Binding IsChecked,ElementName=chk,Converter={StaticResource b2v}}" />
<TabItem Header="World" />
</TabControl>
</StackPanel>
</Window>