Tha'labah bin Abi Malik al-Qurazi (may Allah have mercy on him) says that the Prophet (peace and blessings be upon him) came out one night in Ramadan and saw people praying in a corner of the mosque. He (peace and blessings be upon him) asked: "What are these people doing?" Someone said: O Messenger of Allah! These are people who do not know the Qur'an by heart, and they were praying with Ubayy bin Ka'b (may Allah be pleased with him). He (peace and blessings be upon him) said: "They have done well," or he said: "They have done right." And he did not disapprove of it for them.
This is a good (hasan) mursal report. Tha'labah bin Abi Malik al-Qurazi is from the first generation of the Successors of the people of Madinah. Ibn Mandah included him among the Companions; it is said that he has a narration, and it is said that he was of the same age as Atiyyah al-Qurazi, both of whom were captured on the day of Qurayzah and not killed. He was not a Companion. It has also been narrated with a connected chain, but that is weak.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4611
Sayyiduna Abu Hurayrah (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) came out and saw some people in Ramadan praying in a corner of the mosque. He (peace and blessings be upon him) asked: "Who are these people?" The people said: These are people who do not know the Qur'an by heart, and they were praying with Ubayy bin Ka'b (may Allah be pleased with him). He (peace and blessings be upon him) said: "They have done right, and they have done well."
Abu Dawud said: This hadith is not strong; Muslim bin Khalid is da'if (weak).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4612
Sayyidah Aishah (may Allah be pleased with her) says: We would call the children who were learning to write, so that they would perform the night prayer of the month of Ramadan with us, and then we would prepare roasted meat and halwa for them.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4613