If your child works slower than expected then there are two things you should. Firstly, analyse the plan that you’ve created and have a look whether it isn't just too intense. For instance, several hours per day for multiple weeks in a row will most likely lead to exhaustion and demotivation causing your child to fall behind.
Secondly, have a look at their standard homework and extracurricular activities. Preparing for the 11+ exam should sync in nicely with their current lifestyle and shouldn't cause them to have to drop these other activities. Make sure they eat, sleep and exercise well. A balanced diet, good sleep and regular exercise will boost energy levels and help them concentrate better and for longer periods of time.
However, often times it turns out that parents simply want to move to more advanced topics too quickly. This will cause your child to fall behind when his or her foundation is not yet strong enough. In that case I recommend slowing down a bit on purpose. Take a few steps back and focus on the foundational problem sets.
Changing your planning like that is very common. There’s nothing wrong with creating just a weekly time-table and adjusting it every weekend for the next week. That way you can iterate the revision schedule quickly to your child’s specific progress and potential. I recommend making the revisions schedule one week at a time. Then you can adjust it every week and keep a level of flexibility without feeling bad about it.
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