Home » News Letters

Category Archives: News Letters

Upcoming Events

Recent Comments

Puvidham Narumanam Sep2018

Puvidham Narumanam September 2018

The September 2018 newsletter captures Meenakshi taking a 1 year sabatical, Madhavraj anna taking on new responsibilities, Geetha and Suresh anna inducted into the trust, Sathya anna and family joining puvidham fulltime and many more..

Puvidham Narumanam Sep 2017

Download pdf  – Puvidham Narumanam September 2017


Puvidham Narumanam September 2017

In April 2017 we had a lot of enquiries from parents to host a children’s camp at Puvidham. We decided to have a camp for “Zero Waste Lifestyle” in May. Baladhandapani from Aatrral at Coimbatore stayed with the children for the entire 10 days and showed them how their everyday activities embrace all the science and math concepts that they learn till 6th class. 20 children attended the camp.

We started the camp with a discussion on where the toilet effluent from every city dweller’s house goes. We spoke to the children about how they must make it a point to know where the products they purchase come from and where the waste they generate goes to. The conscious consumer knows the source of the products and their destination after they have been used. The conscious consumer also makes sure that the product is used in creative ways and therefore is never a waste product. And at Puvidham we showed them ways of recycling paper into paper bags or handmade paper, cloth into cloth bags, wash and reusable sanitary pads and foot mats, coconut shells to phone stands and jewellery, egg shells to tortoise and penguin dolls and plastic bags into compressed blocks!

The workshop was designed to help the children to become independent in all aspects. They learnt to cook, clean, care for the cows, sheep and chicken. They learnt how to use very little water and recycle even that to grow vegetables. They learnt to use the composting toilet and understood the advantages of the same in terms of creating healthy compost and prevent pollution of ground water by avoiding use of septic tanks and leach tanks. The children also trekked 8 kms to Piyush Manush’s Coop Forest and met the activist to understand the importance of raising their voices when they see destruction of forests, rivers and lakes and violation of human rights.
We had a parent’s workshop before the children’s workshop for parents who wanted to know about Puvidham before they sent their kids for the workshop. Alongside the children’s workshop, we had two construction workshops for whoever wanted to learn construction with mud. The idea of upgrading the school from 8th to 10th was a long time pending project. We have so many activities and not much dedicated space. So, our thatch roof was removed and we have put a mud and brick dome in its place. We also decided to construct another roof over it to make space for a science lab, a library and a room for origami, painting work and basket weaving.

The school reopened on 6th June and the children came with their energy and laughter. The first day we spoke to the children telling them that since there was construction happening we would be short of space and so we had to reorganize the craft spaces to continue our crafts work. The second day onwards we organized the spaces for uninterrupted craft work. This year a lot of educated parents have opted for Puvidham school. Most of these parents have attended our workshop “Return to the Soil”.
They feel that the environment of happiness, work with nature and scope for autonomy and creative learning at Puvidham is ideal for their children. More than 40 children including 20 of parents who have moved from faraway places to be close to the school and send their children to Puvidham needed to be transported to school every day. Our school Van was not sufficient to transport these children. Finally, in August we went ahead and bought a proper school bus (second hand) and got it registered without having to pay any bribes.

Mr Rajeshwar Rao Dadda, the art teacher from Shanthi Nikethan, got a better opportunity in Coimbatore and left Puvidham with the promise to come for workshops whenever needed.
Palaniyammal the hostel cook had left us in March. Since then Meenakshi and Geetha (a WIPRO software engineer, who resigned her job and has settled near Puvidham in a farm with her husband Mr Suresh Kumar) had been managing the cooking during the summer workshops.

In June, Akila , a parent who attended the parents camp in March decided to join hands to help care for the children in the hostel. She is staying in the hostel with her two kids and she takes care of the LKG UKG section. Mrs Bhuvaneshwari, another parent, decided to help out with the little ones. She has also taken charge of the herb collection and Health drink flour processing work. Mathiyalagan, who has been with us for 3 years now looks after the 1st and 2nd group. Gunavathi came back after maternity leave with her baby and is caring for the 3rd and 4th.

Another parent who has relocated from the US to have their children learn at Puvidham, Mrs Swetha Sriram, joined to help with the 3rd and 4th. Rameshwari is there for 5th and 6th along with the new teacher who joined us in April Mr Perumal. Madhavaraj and Meenakshi are sharing the lessons of the 7th and 8th along with their administrative duties.
Sanjeevi, joined us in July and is under training to be able to take over from Gunavati the following year. Mr Jothi is taking
care of the art and craft work since Rajesh left. He is also the driver for the school bus. We have 35 children in the hostel
and 72-day scholars in Puvidham school this year.
Activities at Puvidham-Surabhi Nivas Hostel:

All the children in the hostel are regularly engaged in the maintenance of the spaces, caring of the cattle, sheep, chicken, dogs and cats apart from weeding the vegetable beds and watering saplings. As we have a lot of new kids in the hostel, it was a bit difficult in the beginning to make them understand the routine and to convince them to do it properly. Starting from the cow shed, cleaning, bathing, washing clothes, cooking and hostel garden work for everything they needed training. So Meenakshi had to continuously be with them for more than a month. Now they are all in a sync and even if no one is there, they do their best. It is planned that one group will get up early for cooking and cleaning the kitchen, the other group will get up for milking the cows and cleaning the Cow shed while a third group goes for gardening. The other children who are younger will wake up a little later and sweep the rooms and verandas, clean the toilets and weed the garden.
The kanji made from 9 sprouted grains and a breakfast of millet upma will be ready by 7.30 am. After breakfast at 8.00 am, the kitchen and vessel cleaning will be shared by the adults and the children. They all then walk to school by 8.30 by which time the day scholars would have been arrived by the school bus and van.

Working with The Elements in School:

As a part of our curriculum we don’t have any maintenance staff in Puvidham. The children are divided into groups to clean the campus and water the plants and provide for drinking water with the help of the adults (teachers) in the team. Instead of prayer we have gardening class for 5th to 8th standard from 9 am to 10 am. Thereafter they go for a walk, have discussions, sing songs, listen to stories, enact plays, work with numbers, draw and paint. Each month we focus on one of the Five Elements and all the stories, songs and experiments are designed accordingly. In the middle we have a 20-minute break for biscuit at 11.00 am and a 45 minutes lunch break at 12.45. After one class from 1.30 to 2.15, the art and craft classes start and go on up to 3.30 pm. The children are divided into vertical groups with each group having children from 6 to 12 years of age. The older children help the younger children to learn the various skills while making different products in the craft classes like soap, herb teas etc. Every month the groups are changed and at the end of the month each group gives an account of the products they made and the cost for each product is worked out! The products made during the craft class are kept in our shop at Puvidham and most of them are already sold out! After this the children and teachers play Traditional games like khokho, kabaddi, kallaatam or cricket, football or volleyball on the school ground. The day ends at 5 pm with a small snack of sprouts and greens prepared by the kitchen group in the school.

Official Business:

The school approval was renewed for the 4th time. We had applied for approval in August 2016. And that finally after changing our roof, putting a fence around the campus and many declaration letters we got the approval to run the school till August 2019. We are thankful to all the officials for finally granting us this permission. The hostel approval had been pending for the last 2 years and finally that also came through for the next 5 years. We can have 50 students in the hostel and run the hostel till 2022. This year from June onwards we have offered an 11-month course for Sustainable living and Entrepreneurship. We had some enquiries but since we are not able to offer a structured program and the Course is a Self-designed learning program no taker so far!
We have also started soil conservation, water harvesting and tree planting work on lands of local farmers who are willing. Geetha and Meenakshi are coordinating the work with the help of NSS students from local colleges.

Geetha is very energetic and keen to make a change in the water situation
in our village. She stayed in Mr Gopal’s farm almost a week in May and with the help of Paramveer college NSS students and has done wonderful  work. They could make pits to store the rain water all around the farm land. Later we planted trees all along the bund where the water stores in the pits will support the plant later.

The Drought :

Year 2016-17 was very dry. The total rainfall was less than our average of 340mm per annum and that too in sprinkles so that there was no chance of the ground water being recharged. So, in May 2017 we were down to the last litres in our wells. The new well in the new hostel land that is closer to Puvidham school was completely dry. The summer was a harsh one and we had to transport water from our old hostel well. Almost every third day 6000 litres were transported by our tractor and trailer. In June when the school started and the hostel had to be run, we rationed water for washing and bathing and recycled every drop to grow some gourds with the used water. It was during this time that we decided to try our luck with a deep bore well at least for drinking water. We drilled up to 600 feet and got only wet granite dust. But after it rained in September the bore has filled with water and we have set up a hand pump to supply clean drinking water.


So, when it came to gardening we decided to make the vegetable beds in our old hostel. Classes starting from 5th to 8th divided their plots and
very nicely have dug up their plot and made nice beds to plant with the help of Rameshawari, Perumal and Madhavaraj. There is a hand pump available. Using this to water their garden manually, they have grown a vegetables, herbs and greens. They learnt the process of digging, making raised beds, manuring, planting, watering, weeding and harvesting. By recording the above activities every day in a diary they learn to calculate the input in terms of labour and seeds, keep track of the output in the vegetables or herbs they harvest and work out for themselves the economics of the farm.
As usual after the first month, in July we had the elections for our children’s parliament. This time Balamurali, who is a design graduate from NID Ahemdabad, came to document the whole process. He is making a documentary film about Puvidham school. He has put down his feelings about his visit to Puvidham in his blog http://eyam.co.in/puvidhamschool-a-children-paradise/


The educational tour for 3rd and 4th class students was organised in end of September to AMIRTHY forest near PADAVEDU, in Vellore District. One of our friend Mrs Rekha and her whole family arranged for the whole trip. All the children were enjoying the tour. We could visit the Amirthy zoo where they saw a lot of wild animals like fox, dear, snakes, a python and different types of birds. From Amirthy forest the 1 km forest walk took us in to a big water falls which was running with red water. Though we could not have bath there we enjoyed the scenery. We stayed in Rekha’s father’s ashram which he designed on his own. The children climbed on the hill near by the ashram and he showed them the very rare endangered medicinal plants. We were missing the water and the swim in the whole trip. Finally, we found a water body in a deserted quarry.
This year during the rains we have planted a thousand Palmyra seeds all along the fence and water collection ponds. All the children worked for two days to get the planting done. We also planted banyan and peepal cuttings and all of them have sprouted! We hope they survive the next summer.
Many parents who have chosen to come to Puvidham because they do not want to stress out their children with exams and rote learning have requested us to upgrade the school till the 10th. The first thing that is needed is space. So, we decided to remove the thatched roof of the Craft room and make a dome with bricks and mud. On top of that we are building another floor. We have started the work with the help of Sabarmani one of our oldest students. He has completed his B.Sc in Physics and done MSW through correspondence. When he was a student in Puvidham in 2004 he had helped Meenakshi with the masonry work of the arches and dome. Since then he has been interested in construction. He has been helping
Meenakshi with some of the projects of mud construction that she did in Conoor. He came to help with the construction of the domes. Mr.Venkateshwaran, a civil engineer, who attended the parents camp and whose children are now studying atPuvidham, worked with him through out to learn the techniques. We are proud to say that Sabarimani is a highly skilled mason and he is a product of Puvidham. He also has had the conviction to build his own house with rammed earth, against the advice of all the neighbours. He is now constructing a retreat with rammed earth and brick and mud domes in Erode.
Now the work is close to finish and we are looking forward to having more organized space for all the young entrepreneurs! We have decided not to go ahead with the upgradation for 10th level. We feel that it is better to write the 10th state board exam as private students or enrol with the NIOS for the 10th and write the exam at the student’s convenience. This would be better than going through the motions of another approval. Besides the infrastructural requirement for the 10th is very intense and we cannot provide it because of paucity of funds.

Financial Support:

As always, our staunch supporter Mr. Manikkam from Dharmapuri through his group called Udhavum Ullangal supports our need for groceries. Mr.Suresh Kumar, who is a Manager in South Indian Bank – In Kovai (Coimbatore) has found good support there and we have a continuous supply of
groceries from his friends. He also runs an NGO in Salem called NIZHAL, through that he organizes feast for the hostel children. Whenever someone celebrates Birthdays, Wedding days and any other functions. He and his wife Geetha both helps in the trust activities in many ways.
The parents workshop “Return to The Soil” that we hold once every month also brings us an average of Rs10,000/- per month. We are also grateful to Ganesan and Swamy to have supported the construction of the buildings, and purchase of the School bus through their circle of friends. Another group called Team India is also supporting the construction activities and we are thankful to Mr. Waran for sourcing funds for the same through his contacts. Our major funds still come from ASHA for Education. They support the running expenses of the school and maintenance of the campus.
Dr. Rajasekhar who is a bird enthusiast sighted some uncommon birds at Puvidham and has sponsored a bird bath at Puvidham. Once the birds become comfortable with the presence of the bird bath and the structure nearby we shall be able to photograph the birds in all their splendour.
Visitors, Trainees and Conferences: A lot of nearby BEd colleges brought their students for field visits to learn about the alternative and innovative practices in education. Around 12 students of MA education and MSW came to observe and learn the practices at Puvidham. Meenakshi travelled to Bihar to a village near Gaya where Anil and Rekha have decided to start their school called Sahodaya. She helped them with the construction of their school and house with mud while training local masons in building arches and a dome. This will become another place for our children to travel to! She attended a National discussion meet on “Gandhian Ideas In Education Policy Perspectives” organised by NEUPA at New Delhi from the 3rd to the 5th of October. She presented a paper under the theme “Curricular reforms based on Gandhian Educational Ideals” and her presentation was called “Education and Sustainability”. It was about bringing in sustainable practices as a part of learning and living as we do in Puvidham. Meenakshi also
attended the Indian Multiversity Alliance Gathering at Udaipur in Swaraj University. Many different initiatives from all over India had gathered to share their experiences with self-directed and self-motivated learning where the certificates became unimportant and life became the examination to prove one’s worth in the field.
Every year we have our plastic collection and segregation drive. This year the children went to Hogenekkal to clean up along with teachers and some parents. Meenakshi went to some of the colleges that visited Puvidham to ask the management to support segregation and collection of plastic waste through an awareness talk with the students imploring them to segregate the plastics in their homes and bring the plastic waste to the colleges from where we shall pick it up. The major incentive for the segregation is lost when people see that the segregated garbage is put in the same pile as the unsegregated one. But if people knew that their efforts in segregation were appreciated and the plastic was being recycled
they would do it with consciousness. She told them about the plastic block making machine and told them that after we had enough blocks we would be making a small house with it – using waste plastic bags as a resource could be a way of recycling them.
As a part of our localization and anti- plastic ideal we have completely stopped purchasing any snacks from big shops. We have found groups which are working with organic farmers and processing millets into murku and laddoos. We purchase these from them and provide these snacks to the children over and above the sprouts and greens. An activist called Nakkeeran went around giving mustard seeds to protest against the GM Mustard. We joined him in the protest and have planted mustard in our gardens.


Puvidham Narumanam – Jan 2017

Puvidham Narumanam December 2017 – download pdf

After the brief rains in July we have had no showers till December 13th when the cyclone hit Chennai. Our rain fed crops have failed and we have lost seed of the pulses that we grow every year. Green gram, black gram, pigeon pea, chick pea and cowpea all were sowed but nothing survived the drought. Our well in the hostel has dried up and we have to transport water for all our activities from the old hostel land. This adversity has made us think of ways of recycling our bath and wash water. We now have a system where all the bath water and wash water is used for growing vegetables, herbs and fruits!

In the second week of October we had a workshop for children to learn about electronics and dramatics. Bala from Aatrral in Coimbatore came with his colleague Sarath Balaji to help the children to get their head around electronics. Bala and Sarath load tested the merry go round mill that we had put together with the help of Gautam from SARANG. It was found that the mechanism would be very strenuous to rotate. So we decided to attach a second hand gear box to facilitate easy rotation. Now it is working and we are able to grind rice flour, idly flour and make khambu and solam rava. The children are able to see how gears work and how human energy can be used to make machines work. The children also attached a cycle dynamo to the charkha to see if they could generate electricity while spinning! Though they could generate electricity with a lot of effort they were unable to do so while spinning! All this means a lot of fun and experimenting with ideas that helps the kids to grow into creative individuals.

Mr Arvind and his team Clay Fingers from Chennai came to teach the children how to play the tappati and helped them to write songs about nature. All the kids and teachers wrote songs about different themes connected with our work in the village concerning the revival of the river Nagavathi. The next week we went to Nagarkoodal village singing the song to revive the river and the people all extended their support for such a project. We are now in the process of writing a project proposal to make this dream a reality!

In connection with this, Meenakshi and Geetha; who has joined the puvidham team especially for this work, went to Rajasthan to see Mr. Rajender Singh’s work in the Alwar district. Mr. Rajender singh is lauded as the water man of India because the work he has facilitated in that region has revived 6 rivers and brought life to the deserted landscape. Geetha made a small documentary in tamil to share with the people of Nagarkoodal. There seems to be much hope and apprehension among the people regarding the water harvesting systems proposed. There is also the general feeling that there is no rain so all the water harvesting work would be a waste. More time needs to be spent with the people to ease these fears and build their confidence in the one and only way in which we can save our agriculture and our livelihoods in rural areas.

On the 12th and 13th of October 55 teacher trainers from Teach For India came to puvidham to learn about our sustainable, minimum waste lifestyle. They stayed in the old hostel building, used the composting toilets and cooked on the smokeless chulha. Meenakshi did a 40 minute Eurhythmy session with them after which there were question answer sessions where they enquired about our teaching methodology and shared their ideas and appreciation.

Towards the end of October we took the 7th and 8th class for a weeklong trip to Coonoor, Gudalur, and Wayanadu. At Coonoor we stayed at Ashok and Malathi’s farm called Sounds of silence and it was indeed a very refreshing experience for all of us. We trekked in the long wood shola in kotagiri. Mr Bhoopathi was our guide but the whole trek was orgainsed by Dr. Rajasekar from Chennai, who is a well-wisher of Puvidham and an ardent bird photographer.

After Bhanumathi akka’s workshop the children had been going to the forest in pairs to observe and make any pictures of birds or insects. They have been very successful in making pictures of birds that we did not even know were around puvidham. When Dr. Rajasekhar subsequently visited puvidham they showed him their pictures. He spoke to children on how to make good pictures of birds by creating a bird bath and a hide out. We have made the platform and Dr. Rajasekar is getting a stone bird bath built which we shall set up on the platform.

In the meanwhile the tree house that the 7th 8th children had started to build after building the small mud playhouse has been completed and is flush with visitors all day, some children, some squirrels and many birds… we have seen the white bellied drongo, the bee eater, the paradise fly catcher, the oriole and of course the sunbirds and the mynas the woodpeckers and the cuckoo. The kids of all ages go up and down the tree house all day. Some read, some sleep. But it is hardly ever empty!

At first it had only a platform. Then we decided to put some kind of a roof. The children of class 7 and 8 wove a bamboo frame and the children of 5th and 6th wove coconut leaves to make a completely weather proof roof!

In November, Emily Mignanelli who is a teacher in a democratic school in Italy, a Montessori teacher and teacher’s trainer and works in University as Professor assistant in General Pedagogy came to puvidham and stayed with us for 10 days to understand our challenges and make a documentary so as to contribute to the actual debate about education and give a new glance on what is a good way of educating children and finding possible ways to support it.

On 13th November Meenakshi and family went to WARDHA to receive the MAA BABA award for taking Nai talim forward in puvidham. This award was given by Mithu Gosh the only child of Asha Devi and Edward Aryanaayakam who started the first Nai Talim school in Seva gram. We all feel really honoured to receive this prestigious award for our humble task.

On November 9th the children of class 5 and 6 left for Marudam farm school to participate in the craft workshop for 10 days. They came back full of new ideas and energy as usual. It was during this time that we suddenly hit upon the idea of using entrepreneurship as a strong core of the learning process for children above the age of 10. We have always been uncomfortable with the textbook reading that we have to revert to because there is no choice for these children but to go back into the system to finish their 10th and 12th. Gandhiji in his Nai Talim has expressed clearly that children must learn through some craft. This year we finally decided it was time for us to take our school forward and try to provide a richer learning experience with entrepreneurship as a core of their learning process. We spoke to the children about it and they were very excited about the whole idea.

As a start we decided up on green businesses like soap making, calendar making, making reusable cloth sanitary pads, cloth bags, paper bags, nursery of herbs and medicinal plants, herbal tea, tooth powder, bathing powder, products from coconut shell like soap boxes, earrings, phone stands, spoons and ladles, puzzles and other learning material. We allowed the children to choose the entrepreneurship of their choice and gave them 3 hours each day to make their products. At the end of two weeks we had enough products to make a tentative sale to see if our children would be further inspired to learn through entrepreneurship. We put up a stall in Dharmapuri on a week end and ended up selling out almost all of the products we had made. It was a phenomenal experience meeting so many people and explaining to them the uses of their products trying to convince them to buy them for the sake of the environment and to boost local economy.

It has enthused the children with such energy that even the children totally averse to reading and uninterested in math have decided to learn these totally uninteresting subjects because they see the application of these in their enterprise! We are now thinking of creating a curriculum around these enterprises where all the concepts that are deemed necessary to be learnt are woven together around the enterprise. We really like this “Avatar” of our school where the children are busy making something and looking for information on how to make them better!

Kunal Kapoor, who is working closely with Prabhakar Pandey, a faculty at the Centre for Alternative Education at Sanchi University of Buddhist Indic Studies spent one month observing how children learn at puvidham. Prabhakar Pandey the head of the department also came and stayed for 3 days and had long discussions on the philosophy and culture and the learning of puvidham.

The school building freshly painted after cementing the roof!

We have to renew our school approval every three years and it was due for renewal. So we had applied for the renewal and had also comply with the new RTE. This required modifications to one of our buildings. Our building had a roof where some of the rooms were tiles over a mild steel under-structure. So we had to redo the roof with ferro cement and then cover it with the same tiles to reduce the heat and also for aesthetic value. We have resubmitted our application for renewal and awaiting approval.

Though the task of redoing the roof cost us money and resources, the building has got a fresh look and it is worth the effort for “those little moments” with “these beautiful individuals”. These tiny tots leave home to come to school around 8.00 before their parents go out to work and reach home around 5.30 when their parents are back home from work! And all the day in the school they are cheerful and have a great time! Just looking at them play cheers us adults up! They are inventing games and creating rules every day. They have a perfect understanding of the quality of the different materials around them and use them effectively to experience bounce, or extend their reach!

The wonderful patterns in nature created randomly by fallen leaves and moss growing on the rock leave us to think how we ended up creating ugly townships and cities!
We all start the new year with a prayer for all the birds and animals that are suffering due to the greed of the human race and hope that more and more people use less and less of the earth’s resources to fulfill their needs and make time to be with nature!

We thank all our donors and friends for their continued support! Do look us up at www.puvidham.in or just come over! If you would like to foster one or more children or contribute to any of the activities, contact [email protected]

Phone: 09600491176 / 09500964830 / 09585759184

FCRA number: 075870079
80G no: c.No:9755(23) / SLM / 2003-2004

Postal address: Puvidham, Nagarkoodal village and post ( via) Indur, Dharmapuri , Pin no: 636803. Tamilnadu. India.

Puvidham Narumanam Oct 2016

Puvidham children were invited to Sustainable Livelihood Instititute to beautify their office building with Warli Paintings


Article in Vikatan – read complete article

புவிதம் – காட்டுப் பள்ளி:

புவிதம், இது அந்த பள்ளியின் பெயர். ஏன் புவிதம்…? அதை பின்பு காண்போம். நான் ஏன் அதை காட்டுப் பள்ளி என்கிறேன்…? நிச்சயம் அது காடுகள் சூழ இருப்பதால் மட்டும் அல்ல. காடுகளில் எப்படி மரங்கள் அதன் இயல்பில் வளருமோ, அது போல்தான் இங்கும் குழந்தைகள் அதன் இயல்பில் வளர்கிறார்கள். குழந்தைகள் மீது எந்த ரசாயனங்களும் தெளிக்கப்படுவதில்லை (ரசாயனங்கள் என்று நான் குறிப்பிடுவது, நம் விருப்பங்கள், பணம் சார்ந்து நமக்குள் இருக்கும் மதிப்பீடுகள், சக மனிதனை போட்டியாளராக கருத வைக்கும் நம் கருத்துகள்). இவை எதுவும் அங்கு மாணவர்கள் மீது திணிக்கப்படுவதில்லை. அதனால்தான் அதை காட்டு பள்ளி என்கிறேன்.


A documentary by Russian Educator on visiting Puvidham


Rahul – A student from Swaraj University – shares his views

Construction of swimming pool, Meenakshi invited to attend the Maverick Teachers International Conferene at Agasthya Foundation – kuppam, Meeting with Butterfly expert Banu etc.,  You may download the newsletter from the following link. Download newsletter Puvidham Narumanam Oct 2016.pdf