Your student could find lots of grammar work on the web by googling various tenses etc. however it can be difficult to identify activities at a specific level.
My site (mark.yates.net/engextra/) provides, for example, exercises on the passive at level 3 units 11 & 12, level 4, units 1 & 2, level 6, unit 3 and level 7 unit 3. There is also a good deal of work with audio and video dictations which include the Nanogong function which students can use to repeat words, phrases or whole completed dictations, comparing their pronunciation with the original.
The advantage of the site is that a range of activities is provided at eight easily identified levels.
Hope this will help,