Sometimes students develop negative mathematical identities because their teachers have had low expectations of them. Placing a student in a “low-ability” group can powerfully reinforce a negative mathematical identity.
Students who struggle in mathematics typically spend more time on skills-based activities than their mathematically confident peers. This means that they have fewer opportunities to stretch themselves intellectually or to develop the resilience that comes from grappling with challenging problems. It can also make mathematics seem boring and irrelevant.
Sullivan (2011), page 42
Students need to become familiar with the pleasure that arises from solving a challenging problem or from making sense of mathematical ideas.
Giving students the opportunity to engage with challenging problems shows that you recognise and respect their capacity to think mathematically.