If you meant (School of the 21st Century) or a similar Russian educational program, here are the solid features you can find on top GDZ platforms:
It seems there might be a typo in your request. "Shkola iuei" doesn't match a standard educational platform, but based on the context of "gdz onlain" (GDZ online), you are likely looking for (Ready Homework Solutions) for a specific school curriculum. shkola iuei gdz onlain
: Optimized interfaces for quick viewing on smartphones during study sessions. If you meant (School of the 21st Century)
: Many sites now include video walkthroughs to help explain complex logic rather than just providing the final answer. : Many sites now include video walkthroughs to
: Includes workbooks (rabochaya tetrad), tests, and control works across all grades.
To get the most accurate "feature" or help, could you clarify the specific school program or textbook you are using?