Sikshana Spoken English - test results on Sikshana's laptop, and how the models were chosen ========================================================================================= A2Z, 3 November 2026 THE LAPTOP Sikshana's test laptop, handed over at the demo on 30 October 2026: Lenovo ThinkPad T14s Gen 1, Intel Core i7-10610U (4 cores, 8 threads), 16 GB RAM, 256 GB SSD, Linux Mint 22.3 Cinnamon (X11), Firefox 158. Everything runs on the laptop, offline. No internet and no admin rights are needed, and no recording of a child's voice is kept. 1. VERSION 2026.11.03 ON THE T14s (3 November 2026) The current package is installed on the T14s. The 4 test children's progress, the teacher PIN and the laptop's settings were kept, and all 8,531 files on the laptop are identical to the package. To leave the laptop's own data untouched, the checks below ran on a copy of the installed app. What Result on the T14s ------------------------------------------- ----------------------------------------------------- Checking what a child said (speech check) 1.3 - 1.6 s per sentence 6 lesson sentences said correctly all graded "great" (98 - 100) A sentence checked against the wrong line graded "try again", as it should be Buddy's first reply of a visit 7.6 s, while the model warms up Buddy's later replies about 1 s each Buddy saying a new 13-word sentence 2.4 s Buddy's 544 most common sentences play at once (recorded in advance) Lesson, game and guide audio plays at once (recorded in advance) Screens all four designs, the pictures and the 37 levels load Updates row in the laptop check "updates are off", as intended in this version The laptop while the app runs: 15.2 GB RAM, 12.4 GB of it free; 180 GB of free disk. 2. INSTALLING AND UPDATING (1 - 3 November 2026) - The package installs with bash install.sh , adds the desktop icon and opens the app full screen in Firefox, with the microphone allowed and no questions asked. - The T14s has been updated four times (2026.11.02, 2026.11.02-b, 2026.11.02-c and 2026.11.03). Children's progress, the teacher PIN and the laptop's settings were kept every time. - On our test machine, the same package was installed over the previous version and on a clean laptop. Both worked, and a test child's progress was kept. - "Report a problem": the two test reports sent from the T14s reached our team over the internet. 3. HOW THE MODELS WERE CHOSEN (benchmark on our build PC) Before we had a Sikshana laptop, each part was measured on our build PC, limited to 4 threads to stand in for a school laptop. On the real T14s, the times are 2 - 3 times longer (compare with section 1). Speech check (OpenAI Whisper, open source, MIT licence), on the app's own recorded lines: model time per line right line accepted wrong line rejected memory base.en 0.4 s 40 / 40 40 / 40 155 MB <- used small.en 1.3 s 39 / 40 40 / 40 325 MB (can be switched on) With other children talking loudly nearby (5 dB), base.en asked for "try again" on 22% of correct answers; in a quiet room, on 8%. A headset with a microphone helps a lot in a classroom. Buddy's conversation model (open source, runs on the processor), scripted test conversations: model tips right asked a question followed off-topic talk time per reply memory Qwen2.5 1.5B 7 / 7 15 / 15 0 1.5 s 1.4 GB <- used Phi-4-mini 7 / 7 15 / 15 1 3.9 s 3.5 GB Qwen2.5 7B 7 / 7 15 / 15 2 6.7 s 5.2 GB The smallest model did as well as the larger ones on these tests, and it is the only one fast enough on the laptops. Buddy also has its own safety rules: rude words, insults and off-topic requests are blocked or turned back to the lesson. Buddy's voice: Kokoro (open source, Apache-2.0), a female voice with an Indian accent. Lesson, game and guide audio: recorded in advance with AI4Bharat Indic Parler-TTS (open source, Apache-2.0), at a learner's pace of about 120 words a minute. 4. NOT TESTED YET - Real children's voices. Every speech test so far used recorded or computer-made voices. This is the most important thing to test in the first classroom trial. - A noisy classroom, with many children speaking at once. - The other laptop models (T480s, T490) and the i3 laptops. They may be slower, but the app works the same way on them. - The audio and the Kannada text, which still need Sikshana's review.