Hi Arjun,

I don't think there is functionality to hide that feature, maybe some code changes would do it. There are various hacks on the Moodle forums as at here https://moodle.org/mod/forum/discuss.php?d=172416 I just googled it from the Moodle forums, so use with caution :-)

In terms of current functionality, a couple of other suggestions.

If the topics are not being used to hide or focus on specific areas, maybe just have a topics format course and restrict to one topic, then have all the content placed in that topic? Differentiate with labels/headers.

Or take a look at Book activity as an alternative way of presenting the information, page by page.

Though if you remove the feature you may get people asking why they canlt hide topics anymore ;-) - you can't keep everyone happy though.

I notice also there are some changes coming to course formats in Moodle 2.3, (as well as some contributed formats) which will make it to Totara 2.4 http://docs.moodle.org/23/en/Course_formats Maybe something in there to explore too?

Thanks

Andy