| 1637.4 | 1523.6 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | JM | WCT | 1746 | 1712.8 | Royal Rapid Challenge 2025 (A) | 4 | 2025-10-04 | R | B | 0 | 0.33 | -0.33 | -3.6 | 0.24 | -0.24 | -4.8 |
| 1581.8 | 1566.3 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | JM | WCT | 1729.1 | 1720.2 | Western Cape Schools - Top Schools 2025 (U13) | 5 | 2025-09-07 | S | B | 0.5 | 0.29 | 0.21 | 3.5 | 0.28 | 0.22 | 4.4 |
| 1562.7 | 1541.5 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | JM | WCT | 1723.1 | 1640.6 | South African Junior Closed Chess Championships 2025 (U10 Open) | 3 | 2025-04-01 | S | W | 0.5 | 0.36 | 0.14 | 2.8 | 0.43 | 0.07 | 1.4 |
| 1551.2 | 1532.8 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | | WCT | 1674.5 | 1589.7 | CT Metro Schools Individual Closed 2025 (U11 Open) | 5 | 2025-03-02 | S | W | 0 | 0.4 | -0.4 | -6.8 | 0.48 | -0.48 | -9.6 |
| 1463 | 1543 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | | WCT | 1605.3 | 1722.7 | 2025 Kraaifontein Open Chess Championships (U12 Rapid) | 5 | 2025-01-04 | R | B | 0 | 0.29 | -0.29 | -3.5 | 0.25 | -0.25 | -5 |
| 1325 | 1296.9 | 20 | 20 | Van Der Merwe, S (Schalk Wolf) | | WCT | 1572.8 | 1528.5 | Western Cape PS Individuals Championship 2024 (U9 Boys) | 2 | 2024-05-04 | S | B | 0 | 0.17 | -0.17 | -2.8 | 0.19 | -0.19 | -3.8 |
