I am currently dissolving a bit indium in hydrochloric acid. The bubbling starts slow (like the speed of tin) and then speeds up to the speed of the dissolution of iron. This is expected based on the electrode potential of indium metal. This reaction is occurring: 2 In + 6 HCl --> 2 InCl2 + 3 H2
The indium chloride solution is then neutralized with sodium carbonate to form indium(III) hydroxide, which is difficult to filter.
Indium chemistry is very boring: only the element is interesting. Reduction of indium chloride by zinc might produce indium powder which can be pressed together to form a piece of indium metal; this could be an interesting demonstration of the softness of indium.