Bring down your academic targets: Start from a lower target and with your support and guidance, increase it gradually. When you bring down their targets and they achieve it, it boosts their confidence to achieve more.

Promptly checking their classwork, assignments and reports. Show interest, they know when your interest in their well-being is genuine

Ensure child is not 'stressed' with house chores or mental issues: I believe greatly that every child should have enough daily housechores, but keep checking to ensure they're effective. Rotate chores where inefficiency has set in. 

Reward success.