If your child is weak in Mathematics, first find the earliest mathematical layer that is no longer reliable. A poor result in the current topic may be caused by an older weakness in number sense, fractions, arithmetic, algebra, symbols, equations, interpretation, or procedural fluency.
Look at where the child first stops being able to work independently. Do they understand the question but cannot calculate accurately? Know the method but choose it at the wrong time? Follow examples but fail on unfamiliar questions? The first recurring breakdown is usually more useful than the latest chapter title.
Start with the Mathematics Learning Hub. For finding and repairing the earliest weak link, use the Diagnostics & Recovery Hub.