Lesson on things people collect... lead in ideas?

Hi everyone. I am in the middle of planning a reading/speaking lesson on the subject of things that people collect (pre-intermediate). I'm a little stuck for a lead-in...

So far my only idea is putting them in to groups of three and having them look at some pictures of things such as Barbie dolls, coins, postcards etc and asking them to discuss what these things might have in common...

Can anyone think of anything better?

Also any ideas on speaking tasks/games relating to this topic would be really helpful too! Thank you :-D

Hi,

you could write the following:

...modern art
...the kids from school
...newspapers for recycling
...information
...postcads / Barbie dolls / stamps
..£10,000 in compensation
etc

and ask the students to think of the verb that fits all the gaps. It might be more challenging than just looking at pictures. After they come up with 'collect', you could comment on its meanings and then say you are going to talk about things people collect as a hobby.