Here are a few yoga poses that can help stretch and strengthen the hamstrings:

Forward Fold (Uttanasana): Stand with your feet hip-width apart and slowly fold forward, bending at the hips. Allow your upper body to hang and reach towards your legs. You can bend your knees slightly if needed.
Pyramid Pose (Parsvottanasana): Step one foot back about 3-4 feet, keeping your hips squared towards the front of the mat. Fold forward over your front leg, keeping your back straight and lengthening through the hamstrings.
Standing Forward Bend with Strap: Stand with your feet hip-width apart and loop a yoga strap or towel around the balls of your feet. Hold the strap with your hands and hinge forward from the hips, keeping your back straight. Use the strap to deepen the stretch by gently pulling on it.
Reclining Hand-to-Big-Toe Pose (Supta Padangusthasana): Lie on your back and hug one knee into your chest. Straighten the leg towards the ceiling, holding onto the back of your thigh or using a yoga strap. Flex your foot and gently pull the leg towards you, feeling the stretch in the hamstrings.
Downward Facing Dog (Adho Mukha Svanasana): Begin on your hands and knees, tuck your toes, and lift your hips up and back, coming into an inverted "V" shape. Press your heels towards the floor while keeping your legs straight, allowing for a stretch in the hamstrings.